The all-rounder was the subject of a three-and-a-half month ban from the Bangladesh Cricket Board following what BCB president Nazmul Hasan described as "serious misbehaviour".
Issues surrounding his participation in the Caribbean Premier League and an alleged altercation with a spectator during a one-day international had led to his absence but Shakib ripped through the Zimbabwe batting line-up on his return in Mirpur to leave the hosts in a dominant position going into the second day.
His six-wicket haul came at a cost of just 59 runs on Saturday, with top scorer Sikandar Raza (51) unable to steer the tourists away from a disappointing first innings score, before Bangladesh reached 27-1 in their reply.
Bangladesh began well at the Shere Bangla National Stadium as wicketkeeper Mushfiqur Rahim caught Vusi Sibanda (six) off the bowling of Shahadat Hossain (1-45 off 14) in the first over.
Hamilton Masakadza (13) became Shakib's first victim in the 12th over before Brendan Taylor (28) fell to 19-year-old Bangladeshi debutant Jubair Hossain (2-58 off 15).
After Taijul Islam caught Taylor at mid-off, Raza added some resistance before Elton Chigumbura (29) was caught by Mominul Haque to mark Shakib's second wicket.
Craig Ervine (34) fell to Islam (1-42 off 13) to leave the tourists on 192-6 before Shakib ran through the tail to wrap up Zimbabwe's innings.
The wickets of Regis Chakabva, John Nyumbu, Tinashe Panyangara and Tafadzwa Kamungozi cost just 48 runs, with Tendai Chatara left on 14 not out.
Tamim Iqbal (five) was the only wicket of Bangladesh's innings before the close, caught by Masakdaza off Panyangara's bowling in the fifth over to leave them 213 behind heading into day two.