Many children were among the dead and at least 50 others were wounded in the explosions that hit two crowded markets and a busy bus station.
The Nigerian Islamist militants have relentlessly attacked Maiduguri throughout their six-year uprising, which has cost more than 13,000 lives and security forces in the city have struggled to contain the bloodshed.
Nigeria has since last month claimed key victories over Boko Haram in an offensive being waged in cooperation with forces from neighbouring Cameroon, Chad and Niger.
A woman with explosives strapped to her body blew herself up at roughly 11:20 am local time when she got out of a motorised rickshaw at Maiduguri's Baga fish market, said the head of the fisherman's union, Abubakar Gamandi, who was at the scene.
"The bomb was devastating because it occurred at a crowded area," said Jamuna Jarmi, a grocery seller.
About an hour later another blast rocked the popular Monday Market, causing chaos as locals voiced anger at security forces who struggled to control the scene.
Just after 1:00 pm a third blast hit a used car lot which is attached to the busy Borno Express bus terminal.
There were indications that the second and thirds blasts were also carried out by suicide bombers but details were not immediately clear.
His figures were confirmed by a nurse at Maiduguri General and a vigilante leader in Borno, Danlami Ajaokuta, whose civilian fighters have been working with military across the northeast in fighting Boko Haram.
