Montoya received the suspension at the NRL judiciary on Tuesday evening after referring to North Queensland winger Kyle Feldt as a "fa***t".
While Feldt lay on the ground awaiting treatment during the Warriors' 25-24 win on Friday, Montoya yelled: "Get up Kyle, you fa***t".
In a statement from the Warriors Montoya said he was "fully remorseful."
Montoya had pleaded guilty to a contrary conduct charge.
"I acknowledge and accept that the comment I made on Friday night is completely unacceptable," said Montoya.