He served as the governor of Surigao del Sur province for three non-consecutive terms from 2001 until 2010 and again from 2016 until his death in office on December 25, 2018.

[2][3] Pimentel began his professional career in politics as a barangay captain in Tandag, the capital of Surigao del Sur.

In 2018, Pimentel filed to run for re-election as governor in the forthcoming 2019 Philippine general election in May 2019.

[2] His younger brother, Tandag Mayor Alexander Pimentel, replaced him as the new gubernatorial candidate.

[2] He died in his sleep the next day on December 25, 2018, at his home in Surigao del Sur at the age of 71.