Abstract: [Objective] To evaluate the application effect of a cashmere production improvement technology by photoperiod control in different local varieties of Mongolian colored cashmere goats. [Methods] Seven local varieties of colored cashmere goats were selected from five provinces of Mongolia. Goats of the same variety from the same region were assigned to experimental group and control group. The experimental groups were reared according to a patent technology of cashmere production improvement. The thickness, yield and fineness of cashmere of goats in experimental group and control group for each variety were determined and statistically assessed. [Results] From 2015 to 2017, for all of the seven selected local varieties of Mongolian colored cashmere goats, the experimental groups showed significantly higher cashmere thickness and yield compared to the control groups （P〈 0.05）; in 2017, for the three tested varieties, no significant differences in cashmere fineness between experimental groups and control groups were found （P〉0.05）. [Conclusion] The technology evaluated in this study has a significant cashmere production improvement effect on Mongolian colored （Red and black） cashmere goats, furthermore, it has no affect on their cashmere fineness.