Two goals in two first-half minutes secured the result, although Cheltenham attacked with gusto at the end following a 74th minute goal from Paul Connor and can count themselves unlucky not to have taken a point from the contest.
It was an evening contest for the first 25 minutes with neither side able to create a great deal.
Walsall defender Richard Taundry saw a free-kick parried wide by goalkeeper Shane Higgs while at the other end, Cheltenham 's Andy Lindegaard brushed the crossbar with a shot from 22 yards.
Walsall took control with two goals in as many minutes midway through the first half, although they were given plenty of assistance by some generous Cheltenham defending.
First, lively midfielder Lee Holmes ran onto a pass from Idrissa Sonko and Higgs, who hesitated at first, dashed out and needlessly caught the man instead of the ball inside the box.
Veteran striker Tommy Mooney made no mistake from the spot.
Two minutes later, Holmes delivered an in-swinging corner from the right and defender Anthony Gerrard got free inside the six-yard box to score with a near-post header.
Cheltenham huffed and puffed but could not haul themselves back into the game until a double substitution by manager Keith Downing changed the shape of the contest.
Almost immediately, Steven Gillespie got away down the left-hand side and crossed low for Connor to slide in and score.
The home side threw everything they could muster at Walsall in the closing stages, but the closest they came to a goal was an angled drive from substitute Michael D'Agostino that flashed wide of the far post.