In order to find out the effects of GABA on the rabbit s intestinal motility, the following experiments were carried out using Magnus method and the results obtained were as follows: 1. GABA inhibited the intestinal motility of rabbits initially. 2. GABA potentiated the inhibitory action of adrenaline and nor-adrenaline. 3. GABA inhibited the accelerating activity of acetylcholine on the intestinal motility by its anti acetylcholine effect. 4. The inhibitory action of GABA was unaffected with atropinization, strychnin, picrotoxin treatment, but the accelerating activity of GABA observed in some cases was only in the picrotoxin treatment.