All-rounder Darren Stevens took six wickets as Glamorgan lost ten wickets for 37 runs after lunch in the Specsavers County Championship match in Cardiff.
In reply, Joe Denly (43) and Zak Crawley (33) shared the biggest stand of the day to help Kent to a lead of 69 runs.
After a watchful first session by the hosts, the new-ball duo of Stevens (6/26) and Matt Henry (4/31) combined to devastating effect in their second spells at Sophia Gardens.
The 42-year-old Stevens claimed his 20th first class five-wicket haul as Glamorgan collapsed on a cloudy morning in the Welsh capital.
He struck with the second ball of the second session after Glamorgan reached the interval at 57 without loss before former Kent second XI player Nick Selman was trapped LBW for 33.
Australia left-hander Shaun Marsh was the next to fall as the Test player nicked Henry to a tumbling Adam Rouse for 3 as the New Zealander picked up his 20th victim in just his third Championship outing.
Stevens bamboozled the Welsh middle order with Kiran Carlson and Chris Cooke trapped LBW either side of a superb in-ducker to remove Aneurin Donald for a duck.
Henry induced the edge of David Lloyd for 4 to secure the second bonus point before mopping up the tail and a third point by removing Timm van der Gugten and Michael Hogan in successive balls.
In reply to Glamorgan’s 94, Kent lost Sean Dickson, Heino Kuhn and Daniel Bell-Drummond in the first 12 overs before Denly and Crawley’s 78-run resistance helped the visitors into the lead.
Harry Podmore will resume on 25 not out after a superb 33-ball vigil to extend Kent’s lead with Timm van der Gugten (6/20) the pick of the home attack, his best figures in his Glamorgan career.