The Kenyan is about to serve a five-match ban after collecting a third red card of the season.
The Kenyan was dismissed during the second-half of the narrow victory against West Ham after making a challenge on Dimitri Payet, which means that he will now serve a five-match ban (via Daily Echo), and Koeman explained that he plans to speak to the former Celtic man regarding his conduct.
"I will speak with Victor," he told the Echo.
"I didn't speak after the game because everybody was so happy about the final result and we have the whole week to analyse the game and to speak about those situations.
"Normally you need to be clever. Of course, we need players like Victor, because they are winning and doing tackles and most of the time it is good for the team.
"Sometimes you can't take this risk what he took on the pitch in the second half."
While there didn't appear to be a huge amount of contact on Payet, the style of the challenge was unquestionably asking for trouble, and thus, Wanyama could have had few complaints when Mark Clattenburg produced the red card.
And while it had no impact on the result against Slaven Bilic's side, his previous dismissal proved very costly as Norwich bagged the winning goal just three minutes after he collected his second yellow, so Koeman will be keen to ensure that the 24-year-old remembers to keep his head in future, as it may prove to be the difference between whether the Saints manage to secure a spot in Europe once again next season or not.