The Brumbies have clinched Super Rugby's Australian conference with a 32-3 bonus-point thrashing of the hapless Melbourne Rebels in Canberra.

Saturday night's four-tries-to-one victory means the Brumbies head into the June international break assured of playing finals for the fifth year running.

Heavy dew made things difficult for players on Saturday night with both sides making handling errors throughout the match.

Despite the slippery conditions, the Brumbies had no problem illustrating the gulf in class between Australia's best and worst performed franchises this season in front of a 8,970 supporters at GIO Stadium.

The Brumbies controlled a scrappy first half and went to the break leading 11-3.

Winger Henry Speight took a quick tap from a penalty on the half hour mark and drew a slew of defenders as he attempted to dive over under the posts.

Two phases later Kyle Godwin found Jordan Smiler out wide, with the No. 8 breaking a 25-game try drought and scoring the only five-pointer of the first half.

The home side made a dream start to the second period with outside centre Tevita Kurindrani bullocking his way through the Rebels' defence to score under the posts, and Wharenui Hawera added the points to extend the lead to 15.

A brilliant run from flanker Chris Alcock just before the hour mark gave halfback Joe Powell the chance to set up Hawera who crossed under the posts before converting his own try to take the Brumbies to a 25-3 lead.

A dashing break from winger Marika Koroibete late in the second half produced the Rebels best chance for a try, but he was denied by Tom Banks and Kyle Godwin metres from the line.

Nigel Ah Wong dived on a loose ball to score the final try of the game in the dying minutes to cap a dominant Brumbies performance.

Hawera notched both his penalty goal attempts while Reece Hodge scored the Rebels' only points of the match with a long-range penalty goal mid way through the first half.