The host Canadians entered the tournament in eighth spot. On Friday, they dropped to 11th.
Only Spain (No. 19, down five) fell further than Canada in the women's top 50.
The Canadian men are currently ranked 103rd by FIFA, having climbed six spots in the most recent rankings.
The U.S. women moved up one spot to top the rankings, changing places with Germany. The Americans thumped Japan 5-2 in Sunday's final in Vancouver to collect the top prize in women's soccer for the first time in 16 years.
France, ousted by Germany in the quarter-finals, remained at No. 3 while Japan was unchanged at No. 4
England, which ousted Canada 2-1 in the quarter-finals, moved up a place to an all-time high of fifth after its best Women's World Cup showing. The Lionesses beat Germany in the third-place game.
In releasing the new rankings, FIFA pointed to Canada managing just two wins against lesser-ranked opposition (China and Switzerland) in five games at the tournament.
The rest of the top 10 was Brazil (up one), Sweden (down two), North Korea (unchanged), Australia (up one) and Norway (up one).
Colombia (No. 25, up 3), Costa Rica (No. 34, up 3) and Cameroon (No. 43, up 10) joined England in reaching a career high.
Cameroon, which rose the most in the new rankings, beat higher-ranked teams in Ecuador and Switzerland at the World Cup and only lost by one goal to Japan and China.
The teams who fell the most were Ecuador (No. 54, down 6) and Zimbabwe (No. 104, down 6)
Six teams (Indonesia, Congo, Moldova, Kyrgyzstan, Gabon and Kenya) re-entered the ranking after long periods of inactivity. Singapore and Lesotho dropped out.
That brings the number of teams ranked to 141, the most since December 2007.
The next women's ranking will be published Sept. 25.
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