Research on the reproduction of snappers helps to manage and conserve them. The spotted rose snapper Lutjanus guttatus is a gonochoric species caught year-round in Navidad Bay, Jalisco, Mexico. This work aims to analyze the reproductive aspects of the spotted snapper L. guttatus caught in Navidad Bay on the southern coast of Jalisco, Mexico. Analyzed fish came from commercial catches. Organisms were sampled monthly from January 1998 to December 2008, and total length, total weight, sex, gonad weight, and gonadal phase were obtained for each specimen. Histological analysis was performed to define the gonadal phase and measure the oocytes' diameter. The total length range in the catches was 14.0 to 61.0 cm; 2889 females and 2792 males were collected for a sex ratio 1.0:0.97. The oocyte development is asynchronous, with a diameter range from 33.9 to 407.9 μm. The testicle is of the lobular type, with a well-defined spermatic duct. A main reproductive season from June to September was identified, although fish with mature gonads were observed in all months. The best condition was observed before the reproductive period. Average lengths at sexual maturity were 30.09 and 30.05 cm for females and males, respectively; the average length of capture in females (32.2 cm) and males (31.7 cm) corresponds to 66.6 and 64.6% of organisms that had reproduced at least once before being captured. Given the importance and continuous capture of L. guttatus in the study area, we recommend further studies to improve the understanding of reproductive and fishing activities.