Aim: As one of the most critical periods in women's lives, pregnancy affects their physical, mental, and functional conditions. These changes can affect the quality of life and sleep of pregnant women. The main purpose of this study is to investigate the effect of Pilates exercises on 140 young pregnant women between the ages of 20-40. Methods: This randomized double-blind clinical trial study was done between September 2023 and March 2024, including 60 pregnant women in case group and 90 control subjects of similar age and body mass index (BMI). This study investigated the effect of 12 weeks of pilates exercises on the quality of women's sleep and life. Quality of life was measured by the short-form 36 (SF-36) and quality of sleep by the Pittsburgh Sleep Quality Index (PSQI). People were randomly divided into intervention and control groups. Pregnant women in the intervention group were required to participate in two pilates sessions per week for 12 weeks from the 20th week of pregnancy. Results: Our results found that quality of life levels were statistically significant higher than case group after intervention compared to control group (p<0.05; 67.19 vs. 54.94). Also, a statistically significant association between the case and control regarding quality of sleep (p<0.05; 5.41 vs. 6.77). Conclusion: It is concluded that performing moderate-intensity pilates exercises for 12 weeks in the last months of pregnancy can increase sleep quality and life.