Abstract: The present paper reports the results of the culture of unfertilized ovaries of rice in vitro. The inducting medium was N6 supplemented with 2 mg/L 2,4-D, 500 mg/L casien hydrolysate and sucrose was 4%. The differentiated medium was N6 supplemented with 2 mg/L Kinetin, 500 mg/L casein hydrolysate and the concentration of the sucrose was 3%. The 4 cultivars and 2 crossed combinations were used as the experimental materials. The experiments were shown the differentiation of the callus occurred amony various cultivars. The induced frequency in the crossed combinations was higher than that in the cultivars. Now 12 green plants and 3 albino plantlets have been obtained. The chromasomes of 11 green plantlets have been examined. Among them, 6 plantlets were haploid (n =12 ) and 5 plantlets were diploid. The embryoids were located in the micropylar end. Some of them possessed the suspensor, similar as zygote embryos. The callus was found from different origin. One of them was originated from haploid tissue derived from the nuclear in the embryo sac. Another was originated from the diploid tissue in the integument or ovary wall. The origin of the callus from the unfertilized ovary was discussed.