The Protection Area of Flora and Fauna La Primavera (APFFLP) located in western Mexico in the state of Jalisco, is one of 19 protected areas in the state decreed. This area is of great interest to be located in the metropolitan area of the city of Guadalajara and the Transmexican Volcanic Belt. However, it has received little attention and there is not a full inventory of its mammalian fauna. The aim of this paper is to list the species of mammals in the APFFLP, highlight its relevance to other protected areas in the state and the country, and richness within the Transmexican Volcanic Belt. Fieldwork was conducted in two periods, December 2004-December 2006, and October 2010-December 2012. The checklist of mammals was obtained using several techniques such as traps and visual records of the mammals and tracks; we used mist nets for the collection of bats. 59 species were recorded, which are covered in eigth orders, 19 families and 48 genera. The order Chiroptera was the most abundant (27), followed by Rodentia (14) and Carnivora (11). The distribution of species shows that 23 are shared with North and South America; 17 with North America; nine with South America and 10 are endemic to Mexico and Meso America. Three species are considered at risk by Mexican regulations: Cratogeomys fumosus, Leptonycteris yerbabuenae and Choeronycteris mexicana as threatened. In conclusion, APFFLP is important for harboring more species and endemic species than other areas considered relevant in the country, besides being an important area of mammal species richness in the Transmexican Volcanic Belt. [ABSTRACT FROM AUTHOR]