摘要[Objective] This study was to analyze the two hydrochemical factors affecting the distribution of Ceratopteris thalictroides, further to provide basis for its habitat protection and population restoration. [Method] Twenty two hydrochemical parameters of 22 sampling sites in Chinas tropical and subtropical zones were respectively averaged for calculating their variation coefficients, of which the two showing significant differences were used for multiple comparisons and correlation analyses via least significant difference and correlation coefficient. [Result] The correlation coefficients of all the 22 tested hydrochemical parameters varied hugely, but only pH value and conductivity showed significantly differences in two water body (type A and type B). Analysis of correlation presented that pH value were positively correlated with conductivity; further the multiple comparisons showed that the significant difference of pH value was higher than that of conductivity. [Conclusion] With regard to the two hydrochemical parameters showing significant differences, pH value influences the distribution of C.thalictroides more.