Investigators said the case began when officers caught a suspect carrying the protected pangolin while waiting to deliver it in Rach Gia Ward.
The five suspects have been charged with violating regulations on the protection of endangered, precious and rare animals.
The seized animal was identified as a Sunda pangolin (Manis javanica), a protected species listed under Vietnam's Group IB classification.
According to police, the case began on June 6 when one suspect found the pangolin, caught it and hid it in nearby bushes before arranging its sale through several intermediaries.
The animal was passed through multiple suspects before reaching An Giang, where it was prepared for delivery to a buyer.
Police arrested the final suspect on June 12 outside An Hoa Park in Rach Gia Ward while he was waiting to hand over the pangolin.