Fisheries represent the principal economic activity in the Northern Gulf of California, Mexico, but few targeted species are managed by any type of harvest controls. This study assessed the sustainability of two main fisheries in the area: fine-scale triggerfish (Balistes polylepis) and leopard grouper (Mycteroperca rosacea) by comparing estimates of annual landings (fisheries production) with the surplus biomass produced on fishing grounds (biological production) of each species. The specific objective of the study was to determine for each species whether fisheries production exceeds biological production, which would indicate that overfishing is occurring. Results of this comparison show that fishing is more than 3 times higher than surplus production for leopard grouper and 15 times higher than surplus production for triggerfish. These results suggest that both species are in an overfishing state.