JERUSALEM—Israel’s Supreme Court reduced the sentence of a Palestinian man convicted of rape by deception for posing as a Jew.

The 18-month sentence imposed on Saber Kashour, 30, was reduced Thursday to six to nine months. His sentencing in July 2010 was part of a plea bargain.

Kashour told the court that his sexual encounter with a Jewish woman in downtown Jerusalem was consensual. The woman filed a complaint after realizing that Kashour was not Jewish. The court ruled that the consent for sex was obtained under false pretenses.

Kashour, a married father of two from eastern Jerusalem with no criminal past, had been released from house arrest pending the appeal’s outcome.