First-half tries by openside flanker Martyn Williams and replacement Harry Robinson got the Blues into a lead which was never truly challenged by the hosts who were in search of their first win in the league in 2012.
Scrum-half Fabio Semenzato captained Treviso and his side set out to test Cardiff's wide game early and the mid-table Blues took time to adjust to it.
When they finally did, via a Dan Parks penalty in the 17th minute, they had the balance of their backline put out of jolt by an injury to wing Richard Mustoe in the 22nd minute. Robinson replaced him.
Cardiff were then pulled level at 3-3 by a Willem De Waal penalty but the Blues are chasing a play-off place and were in no mood to be obliging towards their hosts.
First, Blues veteran Williams ran in for a try on the half-hour mark after a long run up-field by wing Chris Czekaj and Parks converted.
Then replacement wing Robinson made it two in two minutes for his team, and Parks again converted to make it 17-3 at half-time.
A yellow card to Treviso flanker Manoa Vosawai early in the second half for repeated infringements gave Parks a chance at his second penalty and from 40 metres out the former Scottish international bisected the posts.
Trevisomade a host of changes midway through the second half but full-back Brendan Williams and Andrea Pratichetti punctured the Blues' defensive line on separate occasions yet the ball never went to hand.
It took until the 73rd minute for an attack to tell and utility replacement Simon Picone scorched over but De Waal missed the conversion.
Any thoughts that was to be a consolation score were rubbished when the diminutive Williams went over five minutes later to put his side to within a score but again De Waal erred with the extras.
|Benetton Treviso Score Card|
|Willem de Waal||1||3|
|Cardiff Blues Score Card|