The 18-year-old joined Barcelona on loan from Cairo giants Al Ahly in February before making a permanent switch in the summer, having featured at the World Cup.
He became the youngest player to represent Egypt at the World Cup, where he appeared in four of the team's five games.
Abdelkarim impressed in pre-season for Barca with four goals in five matches and made his competitive debut for the Spanish champions as a late substitute in last month's 5-2 win over Rayo Vallecano in La Liga.
He is due to sign his contract extension on Tuesday, the club said.