With one more match played, Hammarby are now two points behind league leaders Häcken, who will meet Eskilstuna later this afternoon.
AIK shocked the second-placed team in the Swedish women's league at Skytteholms IP. In the fifth minute, Haruna Tabata scored to make it 1-0 after Hammarby goalkeeper Cajsa Andersson was at fault for a poor clearance.
Six minutes later, Daniella Famili headed in the second goal from a corner.
Although captain Alice Carlsson reduced the deficit in the 72nd minute, and despite heavy pressure, Hammarby could not find an equaliser and remain on 47 points.
AIK are now fourth in the table with 31 points.
