
What makes the Tuna Mayonnaise Spam Musubi so popular with Japanese convenience store customers?
If someone were to ask us what the most popular type of onigiri rice ball was at convenience store chain Family Mart right now, we’d probably take a guess and say, “salmon” or “tuna and mayonnaise“.
While we’d be right at any other time of year, when these usually are the top-selling flavours, it appears there’s now a new number one, as the Spam musubi has smashed the competition, selling over four million units to date since its nationwide release on 3 August.
The success of the Spam musubi (rice balls are known interchangeably as “onigiri” or “omusubi” in Japan), has been a surprise to many. However, one person not surprised by its popularity is our Japanese-language reporter, Ikuna Kamezawa, who tried a total of eight convenience-store Spam rice balls last year in Okinawa, where the tinned meat is incredibly popular.
Given its popularity in Okinawa, Family Mart has now decided to let the rest of the country get a taste of the action, this time with a new Spam musubi that’s available at all their locations across Japan…except in Okinawa.
▼ Sorry, Okinawa — this is one Spam rice ball you won’t be getting.
While Ikuna was familiar with Spam as a rice ball ingredient due to her experience in Okinawa, most of her colleagues in the office had never tried one, or even seen one, before. Our reporter Saya Togashi said she was particularly keen to get a taste of it, so she popped by her local branch of Family Mart and picked one up to find out what made them so popular.
The bright blue Spam-like packaging immediately jumped out at her, stealing her attention away from the much cheaper 100-yen (US$0.91) onigiri on the shelves. At 248 yen, the Spam Musubi was a much more expensive option, but when she returned home and got out her kitchen scales to weigh the rice ball, she found it was much heavier than most, weighing in at a hefty 180 grams (6.3 ounces).
On the packaging, Saya could see the words “Spam“, “pork & egg“, and “Tuna Mayonnaise” written on it in English, but she was still baffled as to what the combination would taste like. So she tore the package open and took a peek inside.
Cutting the musubi in half to get a good look at the cross-section, Saya could see the layers of ingredients inside. There was a thin slice of egg omelette, a generous layer of tuna mayo, and a thick slice of Spam, all sitting in the middle of a mound of rice which was wrapped in seaweed.
Saya, who grew up in northern Japan, far, far away from the southern island of Okinawa, was a little embarrassed to admit that this would be her first time tasting Spam. She’d never had it on its own, or as part of a meal, so her first introduction to the tinned meat would be inside a rice ball.
▼ Although given the shape of this rice ball, it was more like eating a rice burger.
Saya took a bite and the first thing she said was, “Oh my god, it’s salty!” She’d imagined the meat would have an oily taste like ham or bacon, but it was simple and soft, like eating a processed fish sausage.
After she got used to the texture, she was pleasantly surprised to find it had a homely flavour to it. It was like a rice ball her mum would’ve made for her when she was little, with a simple flavour that makes it easy for anyone of any age to eat.
▼ The rice was a perfect partner for the Spam, and she was impressed to see that it didn’t escape out the sides as she ate it.
It was a lot saltier than she’d expected, but it was incredibly tasty, especially with the tuna mayo, as the acidity of the mayonnaise helped to reign in some of the saltiness from the Spam. It was a good portion size too, as it filled her up nicely, and it wasn’t just her belly that was filled, but her soul too.
▼ No wonder they call this Okinawan soul food!
After trying the Spam musubi, Saya says it’s indeed worthy of the top title as a number-one bestseller, and she hopes it’ll become a permanent fixture in mainland Japan, not just at Family Mart stores but other convenience stores too.
There’s now just one question that’s left to be answered: with this pork-and-egg onigiri unavailable in Okinawa, does that mean there’ll be another job ad for a courier to fly the rice ball to the southern island chain?
Images ©SoraNews24
● Want to hear about SoraNews24’s latest articles as soon as they’re published? Follow us on Facebook and Twitter!
[ Read in Japanese ]










Who makes Japan’s best Spam-style onigiri convenience store rice ball? Let’s find out【Taste test】
We find the best “homestyle” onigiri at a super local chain of convenience stores
Family Mart to celebrate 40th birthday by introducing onigiri with eco-friendly packaging
Are Family Mart’s new “exquisite” rice balls worth the high price tag?
Musings on Okinawa’s canned enthusiasm for all things Spam
The Japanese city where ordering grilled chicken doesn’t guarantee you’ll actually get chicken
Studio Ghibli adds new Jiji’s baby plush toy to its anime merchandise range in Japan
Japanese airlines set to cut fuel surcharges for international flights in September and October
Delta Airlines adds first nonstop flight between Japan’s Narita Airport and U.S. in seven years
Beautiful off-the-beaten-path spot near samurai castle in rural Japan looks like a Monet painting
Tokyo sweets store has a “350% Pudding Soft Serve”, and people are going wild for it
Hello Kitty x Godzilla Happy Meals are coming to McDonald’s, but not in Japan [Video]
Japanese figure skating star Yuzuru Hanyu and Winne-the-Pooh announce crossover merch line [Pics]
This beautiful Okinawa beach gives you the best of both worlds when visiting the prefecture [Pics]
Wagyu ramen for foreign tourists appears in Kabukicho, with a very high price tag
Japanese toilet aims to attract foreign tourists but not everybody is happy about it
New Japanese vending machine at Shinkansen station sells cups of ice on platform
Anime fan in Japan arrested for ordering and cancelling over 4.3 billion yen in anime merch
Starbucks Japan teams up with Traveler’s Company for new stationery and goods collection
Japan’s new beer glass is designed to force you to drink…water [Video]
Beautiful Totoro bonsai figure needs no watering, makes soothing rain showers whenever you want
End of a manga era as Weekly Shonen Jump’s circulation drops under one million
This beautiful rural Japan river is a great alternative to touristy summer retreats [Photos]
Studio Ghibli releases new Kiki’s Delivery Service Jiji music box for anime fans
Tokyo subway installing new ticket gates that don’t accept payment through Suica or other IC cards
Japan now has human refrigerators inspired by Japanese vending machines
Hatsune Miku collaborates with Hokusai’s art in new Vocaloid ukiyo-e illustration series [Pics]
New Shinkansen luggage drop-off system begins in Japan, making train travel even easier
Studio Ghibli releases anime T-shirts that pay homage to one of Hayao Miyazaki’s most personal films
Air-conditioned dress shirts arrive in Japan to save working professionals from sweltering heat
Japanese Shinkansen becomes an overnight hotel for three nights this summer
Cup Noodle unveils first-ever cold-water instant ramen in Japan
Pokémon Center Online designates first Pokémon items that will require Japanese ID card to buy
99-year-old woman rescued while attempting to climb Mt. Fuji
Japan announces sudden 400-percent increase in visa fees for foreigners entering the country
Japan’s human washing machines will go on sale to general public, demos to be held in Tokyo
Studio Ghibli has a new anime out, and there’s only one place in the world where you can see it
Starbucks Japan releases new drinkware and goods for Valentine’s Day
Starbucks Japan releases new sakura goods and drinkware for cherry blossom season 2026
Japan’s newest Shinkansen has no seats…or passengers [Video]
Japanese ninja certification exam attracts 131 candidates from Japan and abroad
Salomon releases Japan-exclusive Mt. Fuji hiking gear that doubles as an amazing souvenir
Put sesame oil in your coffee? Japanese maker says it’s the best way to start your day【Taste test】
Which convenience store onigiri rice balls are the most popular? Survey reveals surprising results
Convenience store onigiri rice balls become even more expensive…but are they worth it?
Which Japanese convenience store sells the best onigiri rice balls?【Taste test】
Survey ranks convenience store rice balls – salmon, sea-dwelling poultry & plants steal the show
Seven new rice ball flavors, including some Nissin collabs, coming to Family Mart this spring
Family Mart releases new rice balls with Bongo, Japan’s most famous onigiri restaurant
Which Japanese convenience store has the best plain onigiri rice balls?
What are Japan’s best, and most unique, regional rice balls?
The difference between onigiri rice balls in Tokyo and Osaka
Which Japanese convenience store has the best salted onigiri rice balls?
Japanese convenience store’s Spicy Tuna rice balls might not be what foreigners or locals expect
7-Eleven under fire in Japan for mysterious holes in their onigiri rice balls
This USB device exists solely to warm up rice balls, and honestly, it does a great job
In celebration of Onigiri Day, we compare rice balls from three different convenience stores
Japanese convenience store issues rice ball recall, foodies would’ve loved to eat them anyway