Central midfielder Pe and captain Aphatsala Chanhthavongxay scored two goals each and Saysamone Inthaphone netted the other one for the winners.
Laos will take on Tajikistan on Saturday (April 27) in their last Group A match to decide the group champions.
The match will be held on April 25 at 8:30pm to accommodate the final of the football event in the Bangabandhu Inter University Sports Champs organised by the Ministry of Youth and Sports at the same venue earlier in the day, that the prime minister is expected to attend.
In today’s game though, Laos got the first success in the 2nd minute as midfielder Pe netted the fastest goal of the tournament (1-0).
In the 13th minute, a misstep by Mongolian goalie Munkhzul Byambatsetseg helped captain Aphatsala Chanhthavongxay to widen the margin (2-0).
Rampant Laos got the third success after eighteen minutes. Aphatsala Chanhthavongxay scored her second goal in the 31st minute of the match (3-0).
After the half time, Laos carried on their domination. In the 50th minute, central midfielder Pe again buried the ball into net with her right foot long range shot (4-0).
Mongolia got another blow while defender Saysamone Inthaphone netted the ball directly with a curved free kick (5-0).
Mongolia, who previously routed Tajikistan by 3-0 goals on April 23, failed to come back in the match.
Loas won the game by 5-0 goals, making a bright impression on the tournament in their first outing.
Bangladesh will take on Kyrgyzstan in the second Group A match to decide the group champions on Friday at the same venue. The match will kick off at 6pm (BST).