The optimum organic acid and temperature conditions were investigated for the preparation of oligosaccharides from agar. The tested organic acids were acetate, citrate, lactate, malate, and succinate and the conditions for oligosaccharides preparation were $0.3\%,;0.5%;and;0.7\%$ organic acid concentrations at $80~120^{circ}C.$ The low concentration of organic acid below $0.3\%$ decreased the degrading ratio and the high concentration up $0.5\%$ could not changed the degrading ratio. Conditions below $100^{circ}C$ was not good for degrading agar. But $100^{circ}C;or;120^{circ}C$ was optimal temperature conditions for agarooligosaccharides according to the organic acid type and concentration. The organic acid concentration was $0.5\%$ and organic acid was the citrate or malate. The treatment time considered optimum was 120$~$180 min. The maximal degrading ratio giving optimum conditions such as $100^{circ}C;and;120^{circ}C;was;35.5\%;and;38.7\%,$ respectively. The agarooligosaccharides prepared by autoclaving at $100^{circ}C;and;120^{circ}C$ were 2$~$7 species oligomer.