Background. A concomitant increase in pregnancy complications has accompanied the growing global trend of excessive weight gain during pregnancy. This study evaluates the effect of ear acupressure (auriculotherapy) on the weight-gaining pattern of overweight women during pregnancy. Materials and Methods. This study was a single-blinded randomized clinical trial conducted between January and September 2022. This study took place in health centers of Qom University of Medical Sciences in Iran. One-hundred thirty overweight pregnant women were selected by a purposeful sampling method and then divided into two groups by block randomization method. In the intervention group, two seeds were placed in the left ear on the metabolism and stomach points, while two seeds were placed in the right ear on the mouth and appetite points. Participants in the intervention group must press the seeds six times a day, 20 minutes before a meal for five weeks. For the placebo group, the Vaccaria seedless label was placed at the same points as the intervention group. A digital scale with an accuracy of 0.1 kg was used to weigh the pregnant women during each visit. Descriptive statistics, independent T-test, chi-square, and repeated measure ANOVA (analysis of variance) test were used to check the research objectives. Results. There was a statistically significant difference between the auriculotherapy and placebo groups immediately after completing the study (1120.68 ± 425.83 vs. 2704.09 ± 344.96 (g);
P
= 0.018), respectively. Also, there was a substantial difference in the weight gain of women two weeks (793.10 ± 278.38 vs. 1090.32 ± 330.31 (g);
P
< 0.001) and four weeks after the intervention (729.31 ± 241.52 vs. 964.51 ± 348.35 (g);
P
< 0.001) between the auriculotherapy and placebo groups. Discussion. The results of the present study indicated the effectiveness of auriculotherapy in controlling the weight gain of overweight pregnant women. This treatment could be used as a safe method, with easy access, and low cost in low-risk pregnancies. Trial Registration. This trial is registered with IRCT20200104046002N1.