[Objective] To research the effects of growth period on the flavoniods content of RADIX OPHIOPOGONIS, and to provide scientific references for the GAP quality control of RADIX OPHIOPOGONIS and development and utilization RADIX OPHIOPOGONIS resources. [Method] Production area of three-year-old RADIX OPHIOPOGONIS in Hangzhou City was studied by in-situ dynamic method. Random collection of Ophiopogon japonicus root tuber was conducted after 0.5, 1, 2 and 3 years of cultivation. After washing, the O. japonicus fresh root tuber was dried at -50 ℃. Flavoniods contents of O. japonicus dry root tubers (RADIX OPHIOPOGONIS) under different treatments were detected by UV spectrophotometry. Correlation rules of the flavoniods contents in RADIX OPHIOPOGONIS with different growth years were analyzed by SPSS17.0 software. [Result] The average content of flavoniods in RADIX OPHIOPOGONIS was between 17.68% and 34.86%. With the increase of RADIX OPHIOPOGONIS growth years, flavoniods content showed extremely significant positive increase (P<0.001). The regression equation was y1=-0.008x2+0.066x+0.046 (R2=0.999), and y2=-5E-08x2+0.047 (R2=0.998). [Conclusion] Growth years of RADIX OPHIOPOGONIS had close correlation with the content of flavoniods. There was scientific basis for the collection of three-year-old O. japonicus in main production areas. Due to the particular climate in the main production areas, root tubers should be collected at one year old; and they were easily decayed in the summer at the second year due to the high temperature and humidity. [Objective] To research the effects of growth period on the flavoniods content of RADIX OPHIOPOGONIS, and to provide scientific references for the GAP quality control of RADIX OPHIOPOGONIS and development and utilization RADIX OPHIOPOGONIS resources. [Method] Production area of ​​three-year-old RADIX OPHIOPOGONIS in Hangzhou City was studied by in-situ dynamic method. Random collection of Ophiopogon japonicus root tuber was conducted after 0.5, 1, 2 and 3 years of cultivation. After washing, the O. japonicus fresh root tuber was dried at -50 ℃. Flavoniods contents of O. japonicus dry root tubers (RADIX OPHIOPOGONIS) under different treatments were detected by UV spectrophotometry. Correlation rules of the flavoniods contents in RADIX OPHIOPOGONIS with different growth years were analyzed by SPSS 17.0 software. [Result] The average content of flavoniods in RADIX OPHIOPOGONIS was between 17.68% and 34.86%. With the increase of RADIX OPHIOPOGONIS growth years, flavoniods content showed ext The regression equation was y1 = -0.008x2 + 0.066x + 0.046 (R2 = 0.999), and y2 = -5E-08x2 + 0.047 (R2 = 0.998). Conclusion of RADIX OPHIOPOGONIS had close correlation with the content of flavoniods. There was scientific basis for the collection of three-year-old O. japonicus in main production areas. Due to the particular climate in the main production areas, root tubers should be collected at one year old; and they were easily decayed in the summer at the second year due to the high temperature and humidity.