Since earlier this month, Nguyen Van Chau, with over 20 years teaching experience, had been luring the two students to a school toilet where he proceeded to touch their private parts, according to the police investigation.
On June 11, the students told their parents, who later informed police.
When the teacher learned he had been exposed, he tried to commit suicide by drinking herbicide, but was later taken to hospital by his family and survived, police said.
He has admitted to the act to police, saying he had found "the two students cute."
Both victims have undergone medical examination to confirm molestation.
Chau is being investigated for "molestation of a person under 16." If found guilty, he could be jailed up to 12 years.
His case, concerning the molestation of underage children, is no anomaly.
A recent survey polling over 1,600 children across Vietnam revealed child molestation, cyber bullying, alongside emotional and physical abuse are priorities they want the country to act on.
A global ranking on child rights last month by KidsRights Foundation, an international aid and advocacy organization, placed Vietnam at 57th out of 182 economies.