In the present study on the self-incompatibility in inbred lines of ten local Indian cultivars (Pusa Chetki, Chetki Long, Aushi, Alipur Local White, Jaunpuri, Half Red, Scarlet Red, Chinese Pink, Desi Red and Khasi Kata) of radish (Raphanus sativusL.), Pusa Chetki, Chetki Long, Aushi, Alipur Local White and Jaunpuri were classed as selfcompatible, Half Red, Scarlet Red and Chinese Pink as intermediate and Desi Red and Khasi Kata as self-incompatible. The highest number of germinated pollen grains and pollen tubes was observed in Pusa Chetki, followed by Alipur Local White, Jaunpuri, Aushi and Chetki Long. The discrepancy in the number of germinated pollen grains in the stigmas may be explained by the inhibitory action of large numbers of self-incompatible pollen grains on the stigma. When two lines, Desi Red and Khasi Kata, were grown under different temperature and photoperiod conditions, no breakdown in self-incompatibility was observed, and the flowering periods of these lines are naturally well synchronized. It is well known that uniform and effective cross-pollination may be of great importance for obtaining a high quantity of hybrid seed in self-incompatible types. To produce single cross hybrid seed, the inbred lines Desi Red and Khasi Kata can be used as parental lines.