In the photo, Justin can be seen having a face-off against Derek Zoolander, who is played by Ben Stiller, with the pair doing their best 'Blue Steel' pose.
'Confident' singer Justin and Hollywood star Ben teased the photo on their respective Instagram accounts on Wednesday (29 April).
Captioning the photo, Justin said: "@benstiller #Zoolander2 #itsawignotmynewhair."
Justin hinted at his cameo in a recent Facebook message, where he told fans: "Working on something big right now in Europe. To learn more follow me on Fahlo. He is so hot right now."
The post referenced a joke from the original Zoolander film.
It is thought that Justin headed to Europe, where the sequel is being filmed, over the weekend to film his part.
Zoolander 2 is expected to hit cinemas on 12 February 2016.
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