A second-half goal from Stenhousemuir secured a 1-0 win for the home side this afternoon.
Michael Ruth had the best chance of the first-half for Sons but his strike was beaten away by Darren Jamieson.
The visitors started the second period on the front foot with a succession of corners but failed to find the breakthrough.
They were made to pay midway through the half when Ross Taylor slid the ball into the net from close range after Jay Hogarth kept out Matty Yates’ free-kick.
Dumbarton were reduced to ten men after Ryan Blair’s second yellow but continued to create with substitute James Hilton having the best opportunity but Darren Jamieson collected his shot.
Sons host East Fife next week.