Abstract: It was infered that β-agkistrodotoxin-binding protein is presumably a novel presynaptic functional protein involved in neurotransmitter release.This paper reported studies on solubilization of β-agkistrodotoxin-binding protein from Torpedo californica electric organ,a tissue rich in synapses.The binding assay of this protein was established using a PEG precipitation method,and its binding properties with 125I labelled β-AgTX was preliminarily determined.The results showed that the density of β-AgTX-binding sites in this tissue is relatively high (much higher than that of rat brain).Bmax is 1580 fmol/mg protein and KD value is 5.5×10-9 mol/L.Triton X-100 was proved an effective detergent for the extraction experiment with a yield of about 50%.Thus a hopeful beginning for isolation and purification of β-agkistrodotoxin-binding protein was accomplished.