Genevieve Gregson has scored her first marathon win, two months after running in the event at the Paris Olympics..

The Queenslander won the Melbourne Marathon on Sunday in two hours, 28 minutes and 13 seconds, beating local Sarah Klein by nearly three minutes. Kate Mason, also from Melbourne, completed the women's podium in 2:34:08.

Genevieve's husband Ryan Gregson finished second in the men's race behind Jack Rayner, who clocked 2:11:49 after winning the Melbourne half-marathon for the past three years.

Gregson finished in 2:13:31 to take another step in his transition from middle-distance events, while New Zealander Christopher Dryden posted 2:18:10 for third.

It was the first time the two winners have run the full distance in Melbourne.

Paris was Genevieve's third marathon and she clocked 2:29:56 for 24th place at the Games, after running on the track at the previous three Olympics.

The 46th Melbourne Marathon festival attracted 42,000 runners, with Bendigo's Andy Buchanan winning the men's half-marathon in 1:01:42 after he also ran in the marathon at the Paris Games.

Leanne Pompeani from Canberra took out the women's race, posting 1:09:01 in an exciting finish.

Adelaide's Jess Stenson, one of Gregson's Paris Olympics marathon teammates, was only two seconds behind Pompeani in second.

Only eight seconds separated first from third, with Paris Olympics 5000m runner and fellow Adelaide entrant Izzi Batt-Doyle completing the podium.