In this work,molecular mechanics and semi-empirical quantum chemistry RM1 methods were used to refine and optimize the geometry of 29 thiobenzene-containg derivartives and then the physicochemieal properties parameters,molecular parameters extracted from the geometric model along with indicator parameters were applied to establish the QSAR model for biological toxicity of thiobenzene-containg derivartives to photobacteria. Based on the multiple linear regression analysis,using software SPSS 13.0,equation was established between biological toxic...