Venom from the scorpion Pandinus cavimanus was obtained by electrical stimulation of the telson (stinger). Total venom was toxic to crickets at 7–30 μg and a paralysis or lethal effect was observed at 30 μg of venom (death at 1.5 μg/mg of cricket). Electrophysiological analyses showed cytolytic activity of total venom on oocytes at 7 μg. HPLC allowed separation of the venom components. A total of 38 fractions from total venom were tested on voltage-gated Na+ and K+ channels. Some fractions block K+ currents in different degrees. By using MS analysis, we obtained more than 700 different molecular masses from telson and venom fractions (by LC-MS/MS and MALDI-TOF MS analyses). The number of disulfide bridges of the telson components was determined. A cDNA library from P. cavimanus scorpion was constructed and a random sequencing screening of transcripts was conducted. Different clones were obtained and were analyzed by bioinformatics tools. Our results reveal information about new genes related to some cellular processes and genes involved in venom gland functions (toxins, phospholipases and antimicrobial peptides). Expressed sequence tags from venom glands provide complementary information to MS and reveal undescribed components related to the biological activity of the venom.