The effectiveness of resting cells of a photosynthetic bacterium, Rhodospirillum rubrum N-1, was investigated on the production of extracellular ${delta}-aminolevulinic$ acid(ALA). The ALA generating system required 3hr-incubation in the presence of 10mg of resting cells per ml to obtain the maximal yield of extracellular ALA. and also, under this condition the effect of ALA inducers, i.e., 30mM levulinic acid (LA) and L-glutamic acid($C_5$ pathway precursor) was relatively higher than that of produced extracellular ALA($83{mu}M$). The volume of system and proper cell density appeared to be important factors for the effective production of extracellular ALA.