A five-star display saw Grimsby chalk up their first home win of the League Two season and end Port Vale's unbeaten run.
Jordan Cook, Moses Ogbu, Luke Waterfall, Matt Green and James Hanson were all on target for the Mariners, who had fallen behind to an early goal from David Worrall.
In a first half where genuine chances were at a premium, the visitors went in front after 13 minutes when Worrall bundled the ball home from a free-kick.
However, their advantage only lasted seven minutes as Grimsby responded through Cook.
After winning his side a free-kick right on the edge of the 18-yard line, the returning forward placed a clever strike under the wall and into the bottom corner.
The scores were all square at half-time but the tide soon turned in Grimsby's favour with Ogbu and Green both finding the goal in quick succession.
Nathan Smith pulled one back for Vale just after the hour mark, but - after a few tense minutes - the Mariners restored full control courtesy of Waterfall's late header and Hanson's third of the season.
Report supplied by PA Media.
