The 31m-long (100ft) fibreglass vessel was found hidden in a jungle area in Timbiqui, in south-western Colombia.
Navy officials said it was the most sophisticated submarine they had found so far, capable of travelling 9m (30ft) below water.
The officials said it could carry four people and up to eight tonnes of cargo, and was ready to launch.
Wanna bet Iran and Hizballah have a few of these - and they're not gonna use them for drugs, neither... BUT PROBABLY A SUICIDE MISSION LAUNCHED FROM LEBANON AGAINST ISRAEL OR THE US NAVY...