The Chilean forward was Arsenal's matchwinner on Saturday - scoring at the end of each half to help the Gunners to a 2-0 victory over Sunderland.
Alexis has netted eight times already this season and Oxlade-Chamberlain says the 25-year-old reminds him of another South American striker.
He reminds me of Luis Suarez when he chases everything down and he makes nothing into something
"He’s a world-class player - everyone saw that at the World Cup," the Ox said. "He’s proved that and he’s played for Barcelona where we’ve all seen what he’s done.
"He’s an unbelievable player and part of his game is his character and his hard work - that’s where he’s got both his goals from today.
"He reminds me of Luis Suarez when he chases everything down and he makes nothing into something. He’s done that for us twice today and he’s scored goals at important times for us."
The weekend's win was Arsenal's second in three days on the road, and Oxlade-Chamberlain was pleased with the team's resolve.
"I think we’ll say we deserved the win," he said. "We dominated a lot of the ball.
"They came out better in the second half than they did in the first and they did make it more of an even game in the second half and maybe we didn’t pass the ball as we would’ve liked.
"It’s always important to make sure, when you’re not passing as well as you would like, that you defend right and grind out results like we did today."Copyright 2016 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source