Saeed Ajmal claimed his 45th wicket of the season in the LV= County Championship to end a determined stand by the Glamorgan second wicket pair of Jacques Rudolph and Will Bragg at New Road.
The Worcestershire spin wizard broke through after Rudolph and Bragg had added 75 in 33 overs during the afternoon session.
Bragg had defied Worcestershire throughout the final day of the meeting at the Swalec Stadium in making 91 not out off 92 overs.
But on this occasion after making 28, and surviving one stumping chance off Moeen Ali, he edged Ajmal to skipper Daryl Mitchell at slip.
Rudolph reached 59 out of 103-2 off 43 overs by tea in reply to Worcestershire's 352 all out.
Ben Wright was unbeaten on nine after giving a chance off Ajmal to mid on when on two with the total on 88.
The home attack had kept a tight rein on proceedings and bowled in typically disciplined fashion before Ajmal's success.
Earlier Worcestershire batsman Tom Kohler-Cadmore had achieved his career best score for the second successive innings.
The 19-year-old had registered his maiden Championship half century when making 56 in the previous match with Leicestershire at Grace Road.
Kohler-Cadmore this time reached 85 and, with the aid of useful runs from the lower order, helped Worcestershire reach 352 all out in 114.1 overs.
Then Worcestershire paceman Charlie Morris quickly dismissed Tom Lancefield as Glamorgan reached 14-1 off six overs by lunch.
Academy product Kohler-Cadmore struck 10 fours and a six and faced 183 deliveries during his 252 minute stay at the wicket.
Worcestershire resumed on 266-5 with Kohler-Cadmore on 60 and nightwatchman Jack Shantry on five.
The pair scored freely in the early stages with Kohler-Cadmore gaining two boundaries off Rory Smith via a thick edge to third man and a handsome cover-drive.
Shantry, who has chipped in all season with the bat, advanced to 17 via a square cut for four off Michael Hogan and a cover-drive for three at Smith's expense.
The pair added 32 before Shantry (17) fell to a fine low catch at fine leg by Tom Lancefield off Hogan with the total on 293.
Ben Cox was dropped on nought at first slip by Chris Cooke off Jim Allenby before the 300 and a third batting point in the 105th over.
The Worcestershire wicket-keeper made a rapid 17 with the aid of three fours before he pushed forward to Allenby and was bowled.
Kohler-Cadmore's fine knock ended five runs later when he was adjudged lbw to Smith.
But then Joe Leach and Ajmal added 30 useful runs for the ninth wicket before both were dismissed with the total on 352.
Leach (17) edged Allenby and was caught behind by Mark Wallace and Ajmal went to sweep Dean Cosker's first ball and was given out lbw.
Hogan finished with 4-73 and Smith 3-98. Glamorgan were left with 25 minutes batting before lunch and Morris broke through in his first over when Lancefield (1) fell to a fine low catch by Tom Fell at third slip.