Abstract: Chuanyou No. 12 is the new medium indica hybrid rice combination with high yield and good quality, derived from Chuanxiang 29A and auto-selecting restorer line Nanhui 12, developed by Agricultural Research Institute of Nanping City, Fujian Province. This new combination has been approved by Crop Variety Approval Committee of Fujian Province in 2007 (Min trial rice 2007011). Few of the combination was introduced in Yushan Town, Jianou City, Fujian Province for experimental planting in 2006. It showed high yielding ability, good fertilization tolerance and lodging resistance, Strong resistance, wide adaptability, medium maturity, good grain quality,and suitability of spreading the cultivation of mono-season medium rice in this town. The study introduces the characteristics of this combination and the cultivation technology of mono-season medium rice