Zambia and Iran are 1st and 2nd following 2-1 and 1-0 Group C wins over Portugal and Costa Rica respectively on Sunday in Jeju.
Coach Beston Chambeshi said he is expecting a tough match in their debut clash at junior level against Iran.
“I watched Iran they are a strong team but every team at the World Cup is a strong team so we just have to tune and focus on Wednesday,” Chambeshi said.
“It is an important match for both Iran and Zambia and the best team will carry the day.
“Obviously we have to attack and get goals but we have to be cautious in defence but we are going for maximum points.”
Chambeshi is also boosted by the return from injury of striker Patson Daka who was substituted in the first half of the Portugal game.
“We might start with 90 percent of the team that faced Portugal,” Chambeshi said.
Victory will see Zambia join Venezuela and hosts South Korea in the last 16 on May 30.
Zambia have reached the last 16 once from two World Cup appearances.
The team reached the knockout round during their second tournament appearence in 2007 in Canada before Nigeria ended their run with a 2-1 win.