The oil well drilling process is subject to unpredictable flows from inside the well, known as blowout. The Blowout Preventer (BOP) is a safety device used to seal the well if a blowout occurs, in order to ensure the safety and isolation of the well. This equipment works through a set of valves with hydraulic or electrohydraulic actuation and failures are very common. Electric-drive BOPs are recent bets to improve the performance of BOPs. This work makes a comparative study of the performance of hydraulic (BOPh) and electric (BOPe) BOPs, focusing on the reliability analysis.