Objective: To verify the effect of 30 sessions of the Pilates Method on the body static posture in the sagittal plane and on the flexibility of the posterior muscular chain of adult women. Method: 10 women underwent 30 sessions of Mat Pilates, taught by a trained professional, three times a week for 50 minutes. The flexibility of the posterior muscular chain through Wells’ bench, and the body static posture in the sagittal plane (anteroposterior trunk balance and the position of the head, pelvis - tilt and drive - and knees) through protocol and software DIPA were assessed pre and post intervention. Statistical analysis, descriptive and inferential, was performed in SPSS v. 20.0. The normality of the scalar data was verified by the Shapiro-Wilk test, being conducted for comparison of the time factor, paired sample t-test and Wilcoxon test for data with normal and non-normal distribution, respectively, where α<0.05. Results: The flexibility of the posterior muscle chain had a significant scalar increase (p=0.007) when comparing pre (26.9±11.1 cm) and post (30.8±10.5 cm) intervention. However, this difference was not observed when analyzed categorically (p=0.063). The static body posture in the sagittal plane did not present a statistically significant difference in the variables analyzed (p>0.05). Conclusion: 30 sessions of Mat Pilates promoted improvement in the flexibility of the posterior muscle chain, however, were not enough to make significant changes in the static body posture in the sagittal plane.