Color is one of the critical morphological features of soils, which can be used as a basic index or proxy to reveal numerous soil physical and chemical properties, processes and functions. Soil color is universally expressed by the Munsell color system, and detected by the visual sense through the match of soil samples with the soil standard charts. However, the errors and bias in soil color readily occur using the current method due to the constrain of the difference in individual vision and variation in optical environment. An objective, quantitative and rapid method to determine the soil Munsell color is urgent to be invented.Here, with the combination of color measurement using the colorimeter, automatic calculation and linear interpolation between the adjacent Value (V) isoplanes, a procedure for the conversion of CIE color to Munsell color was proposed to obtain the soil color conveniently, rapidly and precisely. This protocol includes: (1) CIELAB color values of the samples are measured by the colorimeter; and (2) the color coordinates and the Munsell V values are computed automatically with the program in Python language on a base of the knowledge of the conversion between CIE and Munsell color systems; and (3) the linear interpolation between the adjacent V isoplanes and color conversion chart are employed to assign the Munsell Hue (H) and Chroma (C). 419 color chips from Munsell Soil Color Chart of China and 22 soil and paleosol samples were used to validate the protocol. The Munsell H values of 12 chips using our procedure were different from those in Munsell Soil Color Chart of China, and the measured accuracy reached 97%. Meanwhile, the correlation coefficients in Munsell V and C between the measured values and standard values were 0987 (p<0001) and 0976 (p<0001), respectively, exhibiting a robust significance. For the soil and paleosol samples, the difference in Munsell H between the measured values using our protocol and judged by visual sense is least while a discrepancy in Munsell V and C occurs possibly because of the visual values affected by the visual sense and optical environment. Based on the previous literatures on transformation in soil color between CIE to Munsell color systems, we established a procedure, particularly in making a Python program in order to complete the automatic calculation from CIELAB to the color coordinates and the Munsell V values, and providing a new interpolation method to acquire the Munsell V and C values, to facilitate the rapid and applicable conversion of CIE color system to Munsell color system for soils.