Giroud came off the bench to quickly net twice from Bacary Sagna crosses as the Gunners romped to a 7-0 victory over an Indonesia Dream Team.
The France international striker is likely to face increased competition for his place up front in his second season at the Emirates, as Wenger looks to bring in extra firepower.
But the Arsenal boss had words of encouragement for the former Montpellier man, saying: "I like Olivier very much. He scored 17 goals in his first year in England when he needed to adapt and I'm sure he will respond."
Arsenal were one goal ahead at half-time at the Gelora Bung Karno Stadium after Theo Walcott opened the scoring, but the floodgates opened after the break as Chuba Akpom, Kris Olsson, Lukas Podolski and Thomas Eisfeld joined Giroud in finding the back of the net.
"It's been a very positive night for us," Wenger added.
"Everyone did very well. We played with pace, good passing and technical skill and we could also test some of our young players tonight.
"We were faithful to our game and we were rewarded with seven goals and a very good performance from all the players.
"Although it was only 1-0 at half-time, it became a very big win the last 20 minutes when we changed some players when Indonesia were tiring.
"The difference was our physical power and though there is still a lot of work to do before we are ready for the new season, this is a good start."
Arsenal have now moved onto Hanoi in Vietnam, where they will face the national team in their next pre-season tour clash on Saturday.