Glasgow edged up the Celtic League table but were far from convincing against the struggling Blues.
Glasgow (13) 19
Try: S Lamont
Pens:Howarth 2, Parks 2
Blues (3) 14Try:
N. Robinson, MacLeodDrop goal:
Northampton-bound Sean Lamont scored a wonderful solo try and Calvin Howarth did the damage with the boot as Glasgow opened up a 13-3 half-time lead.
Craig Quinnell replied with a try for the visitors, while Nicky Robinson (twice) and Nick MacLeod added kicks.
Substitute Dan Parks clinched the win, wiping away his RBS Six Nations woes with a late penalty double.
Glasgow had the better of the jittery opening sparring session and they edged in front with a simple Howarth penalty after seven minutes.
He was handed another opportunity from much longer range, but this time the ball drifted wide of the left-hand post.
Glasgow kept up the early momentum and almost broke through when Howarth's perfectly-weighted crosskick was superbly pouched by Sean Lamont.
The chance was squandered, however, when centre Graeme Morrison failed to hold his short inside pass.
Having weathered the storm, the Welshmen hit back positively and they levelled the contest midway through the half thanks to an opportunist drop-goal from Robinson.
Robinson's penalty from 50 metres then flew wide.
And as the pace hotted up, Howarth had the home fans cheering again when he booted his side back in front.
The roars rang out even louder five minutes later as Glasgow created a marvellous touchdown made and scored by Sean Lamont.
First, he found a new gear to leave three markers in his wake while hurtling 50 metres - then he dived over in delight after grabbing the return pass from Howarth, who added the conversion.
The Blues burst back into the contest with a Robinson penalty just seconds after the restart.
He had two further pots at goal in quick succession, but both efforts were off target.
Cardiff stepped up the pressure and lock Quinnell pounced for a try caused by slack home defence.
The tide turned back in Glasgow's favour as Grand Slam lock Robert Sidoli was yellow-carded for killing ruck-ball - and Parks slotted the penalty from 40 metres.
His second strike ended the Blues challenge, but they snatched a consolation bonus point with MacLeod's stoppage time penalty.
Glasgow: R Lamont; A Craig, G Morrison, S Barrow, S Lamont; C Howarth, S Pinder; K Tkachuk, S Lawson, E Murray, J Beardshaw, D Turner, S Swindall, J Petrie (capt), A Wilson.
Replacements: G Bulloch, B Prescott, A Hall, P Dearlove, G Beveridge, D Parks, A Henderson.
Blues: N Macleod; D Dewdney, T Shanklin, T Davies, C Morgan; N Robinson, R Powell; J Yapp, R Thomas, G Jenkins, C Quinnell, R Sidoli, R Sowden-Taylor, M Williams (capt), K Schubert.
Replacements: B Evans, G Williams, N Budgett, N Thomas, M Molitika, N Walne, J Vaughton.