This paper analyzes the genetics of sugarcane biomass yield and heterosis of stalk number and weight using the additive, dominance and additive × additive epistasis model. Results indicate that stalk number is controlled by additive and dominance effects, stalk weight by dominance, epistasis, and their interaction with environment, and biomass yield by additive, dominance, dominance × environment, and epistasis × environment effects. Accessions ROC20, ROC24, and ROC25 had high general combining ability with other lines for stalk number. Yuetang 81/3254, Yuetang 85/177, Yuetang 79/177, and Yuetang 80/101 were good female lines with ROC20 and ROC25 as male lines and Yuetang 85/177 × ROC25 was the only superior cross combination.