The objective of this study aims to assess growth capacity of the different Mong chicken lines kept in Ha Nam province. The research was carried on comercial chickens of male and female line as well as the crossbreed line between male and female line. Each experiment had been repeated three time with 50 chickens/repetition. The survivability, body weight, feed conversion ration of the chicken were recorded. The result showed that the survivability of 20 weeks old chicken of male and female line as well as the crossbreed line between male and female line were 92,67% %, 91,33% and92,67%, respectively. The body weight of 20 weeks old chicken of male and female line as well as the crossbreed line between male and female line were 1983,33g/chick; 1741,33g/chick and 1908,34g/chick, respectively. The Feed conversion ratio at 20 old weeks male and female line as well as the crossbreed line between male and female line was 5,49 kg, 6,61 kg and 5,53 kg, respectively