Walcott was linked with leaving the Gunners throughout the summer and has struggled for match action so far this season.
The England ace is yet to start a Premier League game this term but has impressed in cup fixtures.
He netted a brace in Arsenal’s 4-2 Europa League win over BATE Borisov on Thursday and will be eager to be involved against Brighton tomorrow.
Wenger has hailed Walcott’s attacking strengths, suggesting the 28-year-old still has a prominent part to play for the north Londoners.
Wenger said: “I believe his strength is to score goals. He can score goals, he’s a good finisher.
“He had two or three more chances but as long as the team played well he had plenty of chances.
“He has a good quality, it’s the timing of his runs and the quality of his runs. He goes into areas where he is dangerous.
“You want [strikers] to make the right decision in front of goal.
"Sometimes the right decision is to give the ball and when the right decision is to take your chance, take your chance.
"But overall, all the strikers need to be a little bit selfish.
"I don’t like this word but you do need to believe that you will score."
Arsenal, who best West Brom 2-0 last time out in the league, welcome Brighton to the Emirates tomorrow lunchtime.
