The 20-year-old Slovak has yet to play for Fulham's first team, but made 17 appearances in the National League on loan at Welling last term.
Rodak, who has represented his country at youth level, will go straight into Accrington's squad for their League Two fixture against Cheltenham on Saturday.
Stanley are 20th in the table, four points above the relegation zone.
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Accrington Stanley have signed goalkeeper Marek Rodak on loan from Fulham until the end of the season.