Police have dropped their investigation into a Melbourne principal who was filmed dragging a primary school aged pupil along the ground.

Steve Warner, the executive principal of Manor Lakes P-12 College in Wyndham Vale, was stood down after video footage of the incident involving a nine-year-old boy emerged last month.

Victoria Police confirmed on Tuesday it was no longer looking into the January 31 incident as no criminal offence had been detected.

An investigation into the footage by the Department of Education is ongoing and expected to be completed in the coming weeks.