The first 25 minutes went scoreless at AMI Stadium but the home side soon broke open the floodgates with three tries from Robbie Fruean, Kieran Read and Johnny McNicholl that saw them to the half-time break with a healthy 22-9 lead.
Morne Steyn kicked three penalties for the Bulls to keep them in it, and also cut the deficit to 10 with an early goal after the break but it would be as close as the visitors got.
Tom Marshall and Wyatt Crockett both ran in five-pointers to see the Crusaders' lead balloon out to a match-winning one.
Deon Stegmann scored a consolation try for the Bulls, and Steyn's conversion took him to 14 points for the match.
Willi Heinz wrapped up the victory nicely for the home side with their sixth try of the night, and Dan Carter's conversion saw him to an 11-point tally.
The victory snapped a two-match losing streak for the Crusaders, who moved to seventh on the table with 11 points, while the Bulls still hold the lead in the South African conference on 13 points.