Rhinos led by only four points at half-time and the game was in the balance until midway through the second period, but Leeds ran in four late tries to give the final sciore a flattering look.
Though it was comfortable in the end, Leeds endured some anxious moments, particularly at the start of the second half when Stan Robin dropped the ball with the line at his mercy when he was on course to cross between the posts.
A converted try would have edged the French side ahead and set nerves among the home fans jangling, but that was Toulouse’s last opportunity to get something from the game, though they did enough to suggest they won’t be easy-beats in this competition, whoever they play.
Rhinos’ win was only their second in 10 games and they will have to play better to be confident of avoiding relegation, or the million pound game.
The hosts scored first through Brad Dwyer who went over from acting-half after Dom Crosby - who had a big game - had been tackled just short.
Liam Sutcliffe converted, but Toulouse hit straight back through Bastien Canet who went over from dangerman Johnathon Ford’s pass.
There was no goal and Rhinos rallied through a brace of tries from Joel Moon, playing at centre.
Moon, who will return to his native Australia when his contract expires at the end of the season, twisted over from Myler’s pass and then put on some footwork to cross after being given the ball by Sutcliffe.
The first try was converted and Leeds went 16 points clear when Myler pounced on an error to put Ryan Hall over.
Toulouse got back into the game when Ford’s kick, aimed at touch, bounced off Tom Briscoe’s backside, was hacked on by Paul Marcon, hit a post - as Hall was about to collect - and touched down by Bassier Ader.
With two minutes left in the half Maxime Puech went over from William Barthau’s pass and Mark Khierallah converted the second and third tries to make it 20-16.
Toulouse would have gone ahead early in the second half had Robin held on to Khierallah’s pass.
That was a big moment in the game and Rhinos opened a two-score gap on 55 minutes. They were lucky to get a scrum after Paul Marcon was ruled to have knocked on in Myler’s tackle, but Dwyer nipped over from acting-half in the resulting set and Sutcliffe converted.
Eight minutes later Myler stretched over from Dwyer’s pass after Brad Singleton had been held up over the line.
Adam Cuthbertson powered over from Myler’s inside pass and then Carl Ablett, captain on the day, crossed from Dwyer’s offload.
Chris Centrone scored a deserved consolation try for Toulouse, improved by Khierallah, but Ashton Golding scored on the final play on the game.
He was playing on the wing after Hall went off injured.
Sutcliffe finished with six goals from nine attempts. Myler and Dwyer were influential for Rhinos and Centrone impressed for Toulouse, along with Barthau and Ford.