Abstract: The cumulative yields of 95Zr, 99Mo and 147Nd in the fission of 235U induced by neutrons of spontaneous fission of 252Cf were determined absolutely by radiochemical method.In Nov. 1978, the weight of 252Cf used as the neutron source of spontaneous fission was 100 μg, which was sealed within aluminium cylinder tube. When irradiated, the distance from the targets to the neutron source was about 5 cm.The sample targets were highly enriched uranium 235U (90%). The standard targets were prepared by molecular plating and the sample targets were uranium metal disks with masses from 2 to 3 gramms.The absolute fission rate of the sample target was measured by double fission ioni-zation chamber as described in a previous paper6.The cumulative yields determined are listed in following table:The errors given in the table are total errors including statistical and systematic errors. The yield values of 95Zr, 99Mo and 147Nd in the fission of 235U induced by neutrons of spontaneous fission of 252Cf are found to be in agreement with the yields induced by fission spectrum neutrons of 235U within error limits.