The Hammers will take on Palace away from home at Selhurst Park in the Premier League after the international break.
“I’ve got good memories there – I scored on my West Ham debut at Selhurst Park last year – and I hope for another goal this time,” Zarate wrote on West Ham’s official website.
Zarate has scored one goal and created five chances in four Premier League appearances for West Ham so far this season.
The former Velez Sarsfield star has a pass accuracy of 84% and a shot accuracy of 67%, and has won six dribbles and four tackles.
The 28-year-old, who can also play as an attacking midfielder, has struggled with injuries for most of the season so far, but he featured in the Hammers’ last two Premier League games.
The Argentine attacker played the last 10 minutes against Norwich City at the Boleyn Ground and the final 12 minutes against Sunderland at the Stadium of Light.