A histoenzymological study has been carried out on the distribution of enzyme acetylcholinesterase in the optic tectum of two Indian air breathing teleosts by employing a histochemical technique to visualize acetylcholinesterase containing neurons described by Hedreen, JC (1985). Data available on enzyme localizaton in the brain of fishes, particularly Indian teleosts is inadequate and scattered. AChE distribution in the optic tectum shows a prevalent pattern characterized by precise laminar distribution of enzyme which shows alternatively strong, weak or negative reaction in the different layers. Layers with maximum enzyme activity most likely correspond to areas where cholinergic mechanism is prevailing whereas layers with mild activity may be considered to be non-chalinergic/cholinoceptive having some cholinergic innervations from other layers. The present investigation suggests some possible connections between enzyme localization and functional and anatomical organization of optic tectum.