Effect of various auxins on the growth of gall and normal tissues ofProsopis cineraria (Linn.) Druce induced byLobopteromyia prosopidia Mani has been discussed. Differential response of gall and normal tissues to various auxins was observed. α-Naphthalene acetic acid (8 mg/l) and indole-3-acetic acid (4 mg/l) sustained excellent growth of gall and normal tissues respectively. Biochemical studies revealed hypoauxiny and high indole-3-acetic-acid oxidase activity in the gall tissues which have been discussedin vitro andin vivo conditions.