In Mexico, information about ocelots is limited, which hinders the implementation of effective management and conservation measures. The purpose of this research was to provide basic information of population density, relative abundance and home range observed for the species in northwestern Mexico. Systematic sampling was implemented from January to December 2015 using photo-trapping as tool. Fifty-four camera-trap stations (37 double stations) were used, and the resulting grid covered an area of 182 km2. We applied six sampling periods of 59-62 days in each period. Density analysis was based on spatially explicit models and traditional capture-recapture models. The home range was estimated using the minimum convex polygon method. We obtained 135 photographic records of ocelots, of which 17 individuals were identified (five males, four females and eight individuals of undetermined sex). During six study periods, our sampling effort reached 19 710 trap-days. We estimate a capture rate for the study of 6.84 rec./1000 trap-days. The density of ocelots estimated with the Capture module in the MARK program ranged from 1.38 to 2.93 rec./100 km2. The results estimate using the SERC method showed a density of 0.93-3.06 individuals per 100 km2. The ocelots in the Northern Jaguar Reserve (NJR) had an average distribution area of 14.1 km2. The results of this research illustrate the importance of continuing studies of ocelots on the NJR to maintain a long-term viable population for northwestern Mexico.