A regular across global franchise leagues, Woakes has previously featured in tournaments such as the IPL, Big Bash League, and ILT20. His arrival is expected to significantly strengthen the Sylhet Titans squad as they head into the business end of the tournament.
The 36-year-old has represented England in all three international formats and is a World Cup winner in both ODIs and T20Is.
In 33 T20 Internationals for England, Woakes has scored 147 runs at a strike rate of 125.64 and taken 31 wickets. Across all T20 cricket, he has accumulated 1,031 runs at a strike rate of 128.55 and claimed 179 wickets in 170 matches.
Sylhet Titans already boast several overseas stars, including England all-rounder Moeen Ali, Ethan Brooks and Salman Irshad.
Led by Mehedi Hasan Miraz, Sylhet Titans confirmed their playoff spot after a six-wicket victory over Rangpur Riders on Monday.
With five wins from nine matches, Sylhet currently sit third on the points table. Rajshahi Warriors and Chattogram Royals have also booked their places in the playoffs.