The chemical structures and physiological functions of spider pepude neurotoxins have been reviewed and introduced. These neurotoxins can be classified briefly, into two groups according to their size. The short spider neurotoxins contain 33 to 40 amino acids residues, whereas the long ones have 66 to 77 residues. The homologies of the neurotoxins from different species are not evident and the physiological activities are quite difftirent. Some spider neurotoxins were found to selectively affect the sodium or calcium channels of the neuro-muscular system of the insect and vertebrate and were believed to be useful as tools in neurophysiology and pharmacology studies.