Heloderma horridum horridum commonly known as the scorpion lizard, Mexican scorpion, and beaded lizard, is a venomous reptile native of America. The venom derived from this lizard has potential applications, particularly in treatment of type II diabetes through the peptide Exendin. In this work, H. h. horridum venom was extracted from adult specimens and lyophilized. To characterize the venom, enzymatic assays, including hyaluronidase, phospholipase A2, and proteolytic activity were conducted. A proteomic analysis of the venom was also performed employing bottom-up/shotgun approaches from SDS-PAGE and High pH Reversed-Phase chromatography., besides fractionation of tryptic peptides using a nano-LC-MS/MS. These approaches involved massive sequencing to enhancing the likelihood of detecting an extensive range of venom proteins. The proteins and peptides found in H. h. horridum venom are reviewed according to the classification of the transcriptome previously reported.