The Roos’ victory in the two-day match at Breckler Park on Saturday moved them to 12th, sending the Hawks down to 13th.
The visitors had four wickets remaining when they overtook the hosts’ 245 before finishing the match on 314.
Three half centuries contributed to the chase, with top scorer Jordon King striking 72, Bailey Nylander knocking 62 and Tristan Hobley adding 50.
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Wanneroo faces Subiaco Floreat (6th) in the final round of the season this weekend.