Three continuous cell lines, NIAS-PRC-819A, NIAS-PRC-819B, and NIAS-PRC-819C, were established from the pupal ovaries of the common white, Pieris rapae crucivora Boisduval (Insecta, Lepidoptera, Pieridae). The primary culture was initiated as explant cultures with ovariole fragments in MGM-464 medium supplemented with 20% fetal bovine serum at 25° C. About 6 mo after the culture was set up, the first subculture was prepared. Thereafter, cells were subcultured with decreasing passage intervals, resulting in a cell population that multiplied continuously. The karyotypes of these cell lines were similar to each other, and the majority of the cells showed about 100 microchromosomes. The population-doubling times of these cell lines were 3 to 7 d. The cell lines were susceptible to a microsporidia, Nosema bombycis. Immunodiffusion experiments proved that these cell lines derived from the common white and not from other cell lines by contamination.