In this study, machinability of vermicular graphite cast iron with different micro-structure was investigated and modeled with regression analysis the effect of cutting parameters on cutting farces and surface roughness. Machinability experiments were carried out at constant cutting depth for three different feed rates and four different cutting speeds. The experiment results showed that in order to define detailed the values of cutting force and surface roughness multiple regression analysis, SPSS 15.0 program was used, should be used. In the determination of microstructure (perlitik, ferritic, ferritic + pearlitic), cutting speed and feed rate effects on cutting force and surface roughness ANOVA (analysis of variance) table was used. As a result, parameters affecting the cutting force and surface roughness were defined and mathematical model was developed. It is defined that both of the developed models has 95% accuracy ratio and they can be used.