The attack came hours after the Red Cross said a gunman killed two of its Yemeni employees in the war-torn country's rebel-held north in a "deliberate" attack.
The Islamic State group said a man identified as Qusai al-Sanaani blew himself inside the mosque in the northern Jarraf district after sunset prayers.
In a statement on Twitter, the radical Sunni Muslim IS added that a bomb-laden vehicle parked nearby exploded as medics arrived on the scene.
IS, which considers Shiites to be heretics, has claimed similar bombings of other Shiite mosques in Sanaa as well as in Kuwait and Saudi Arabia.
Its account of the attack was confirmed by sabanews.Net, the website of the Iran-backed Shiite Huthi rebels that control Sanaa.
Medical officials said at least 28 people were killed and 75 wounded, and the rebel website said that figure was "not final".
An AFP reporter heard two loud explosions followed by many sirens as ambulances rushed to the scene.
Body parts were blown several metres (yards) away from the scene and nearby buildings were damaged, witnesses said.
Jarraf district is home to many senior Huthi figures, and the Al-Muayad mosque is among their main places of worship in Sanaa.
Earlier today, the International Committee of the Red Cross said a gunman killed two of its employees in an "appalling" and "brutal" attack.
The pair had been travelling north of Sanaa with two other colleagues in vehicles "clearly" marked with the Red Cross emblem, said the Geneva-based ICRC.
"Sadly, two of our staff were brutally killed on their way back from Saada to Sanaa," spokeswoman Rima Kamal said.
Kamal said the unidentified gunman opened fire on the two vehicles after stopping them in Amran province, which has been under Huthi control since last year.
"One of our colleagues passed away on the spot while another sustained critical injuries and was transferred to an MSF (Doctors Without Borders) hospital... Where he passed away shortly after," she told AFP.
The two others were unharmed.
You’ve reached your limit of {{free_limit}} free articles this month.
Subscribe now for unlimited access.
Already subscribed? Log in
Subscribe to read the full story →
Smart Quarterly
₹900
3 Months
₹300/Month
Smart Essential
₹2,700
1 Year
₹225/Month
Super Saver
₹3,900
2 Years
₹162/Month
Renews automatically, cancel anytime
Here’s what’s included in our digital subscription plans
Exclusive premium stories online
Over 30 premium stories daily, handpicked by our editors


Complimentary Access to The New York Times
News, Games, Cooking, Audio, Wirecutter & The Athletic
Business Standard Epaper
Digital replica of our daily newspaper — with options to read, save, and share


Curated Newsletters
Insights on markets, finance, politics, tech, and more delivered to your inbox
Market Analysis & Investment Insights
In-depth market analysis & insights with access to The Smart Investor


Archives
Repository of articles and publications dating back to 1997
Ad-free Reading
Uninterrupted reading experience with no advertisements


Seamless Access Across All Devices
Access Business Standard across devices — mobile, tablet, or PC, via web or app
