Their 6.11 (47) to 6.4 (40) victory at Henson Park in Sydney on Saturday lifted Freo two spots to 10th, leapfrogging Port Adelaide and Geelong.
The Dockers trailed at all three breaks, but were never more than 10 points behind.
The deficits were due to wasteful kicking, with the visitors' score reading 1.7 and 2.10 at different stages, but they kicked three goals in the final quarter to secure a much-needed win.
Freo dominated most of the key metrics, winning contested possessions by 30, clearances by 14, and logging 18 more inside-50s.
"It was a whole team effort, to really grind it out," ruck Mim Strom told Fox.
Strom was outstanding, logging 23 disposals, 28 hitouts, eight tackles and six clearances.
Midfielders Gabrielle Newton (28 touches, nine tackles, six clearances) and Kiara Bowers (22 touches, 10 clearances, nine tackles) were also impressive.
As the game wore on, Freo did a better job of slowing the Giants' ball movement, limiting the home team's opportunities and pouring on the pressure through repeat entries and more accurate kicking.
"A big relief, pretty close but a really hard-fought win, so those are really satisfying when you have to fight to the end," Newton told Fox.
Tunisha Kikoak was Fremantle's only multiple goalkicker, booting two majors.
Most of the Giants' scores, including all 21 of their first-half points, came from turnovers, fast ball movement and some high-quality finishing.
Tarni Evans kicked two goals, one following a low diving "slips-catch" mark, and Cambridge McCormick split the big sticks with a monster kick from more than 50 metres.
Emily Pease accumulated a game-high 29 disposals for GWS, who suffered their fourth straight loss and stayed 15th on the ladder.
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