In order to explore the differences between the laser method and the pipette method on the conversion of soil particle size distribution(PSD)of a single parent material，and to improve the conversion accuracy of the two methods for determining soil PSD，55 soil samples of 0-20 cm of loess-like parent material from Haiyuan County of Ningxia Province and 41 soil samples of 0-20 cm of loess-like parent material from Binzhou of Shandong Province were collected，soil PSD was determined by using the two methods to establish the model of the conversion relationship，and it was verified by using the data from the literature. The results showed that:(1)Both methods showed highly significant correlations between the sand，powder and clay content of loess and loess-like matrices，and a conversion model was developed for particle size conversion. The correlation coefficients of the two methods for the determination of sand，powder and clay content were 0.7980，0.7120 and 0.6850 for the loess matrix and 0.8970，0.7919 and 0.8223 for the loess-like matrix，respectively，and the correlation between the two methods for the determination of the three particle sizes of the loess-like matrices was higher. (2)According to the established spatial right-angled coordinate system，the calculated contribution values of each grain level of loess matrices，loess-like matrices and mixed matrices affecting the overall error were all the largest for clay grains. The loess matrices，loess-like matrices and mixed matrices conversion models all used clay grains for the difference subtraction method in order to reduce the conversion bias. According to the contribution value of each grain level to the overall error obtained from the calculation，selecting the grain level with the largest contribution value for the difference subtraction method could improve the conversion accuracy.(3)Using a conversion relationship model for the PSD of the same mother materials，the consistency rate between the laser method and the pipette method texture was 78% for both parent materials；and another parent material conversion model was used for the conversion，with a consistency rate of 44% for loess parent material texture and 20% for loess-like parent material. By using the same parent material conversion model，the conversion accuracy of laser method to straw method texture can be improved. The laser method could be used as an effective tool for rapid determination of soil texture based on the identical mother material transformation relationship modelling.