The results on horticultural characteristics of parental inbreds and hybrid variety showed that hybrid variety ASVEG # 1 performed better than two parental inbreds i.e. shorter number of days to maturity, bigger head size and higher head shape index. Also, hybrid variety ASVEG # 1 showed higher plant weight, head weight and number of nonwrapper leaves. Sowing date of B-18 inbred was seven days before E-7 inbred when the highest hybrid seed yields were obtained from both parental lines. The results on pollination behaviors of the parental inbreds showed that the E-7 inbred was stronger in self-incompatibility than the B-18, this was due to lower seed set from selfing the intact and the flowers at anthesis of the E-7 inbred. Furthermorre, the E-7 inbred produced less selfed seeds from sibbing pollination than the B-18. In the E-7 inbred population, the homozygosity was higher than the B-18. Spraying of 2% sodium chloride (NaCl) solution before self- pollination after anthesis showed best results of breaking self- incompatibility in the two parental inbreds. Although the application of isozyme esterase (EST) showed the best banding expression, it can not be used to indicate the hybridity in this cross of Chinese cabbage. This was because of the same banding type in the B-18 inbred and the hybrid variety ASVEG # 1.