Studies have shown that postmenopausal breast cancer survivors are more likely to be sedentary and have poorer diet quality than their non‐cancer counterparts, contributing to weight gain. In addition, they are more likely to have increased levels of psychological stress. Heightened mindfulness is associated with healthier eating behaviors, lower BMI, and reduced stress. However, little is known about the effect of mindful eating on these lifestyle factors in overweight and obese postmenopausal breast cancer survivors. The objective of the study was to examine the effect of a mindful eating intervention on lifestyle factors, including mindfulness, stress, and nutritional intake in overweight and obese postmenopausal breast cancer survivors. Participants were recruited through local physician's offices, cancer support centers, and newspaper advertisements in 2016. Participants completed 8 weekly 2‐hour Mindful Eating Workshop© group sessions, led by a certified mindfulness instructor. The workshop addressed mindless, stress‐related, or emotional related eating, and disordered eating patterns through mindfulness meditation and group discussion. Data were collected at the University of Georgia Clinical and Translational Research Unit at 2 time points: baseline and follow‐up (week 12). Nutritional intake was assessed using the 2014 Block Food Frequency Questionnaire. Mindfulness was assessed using the Mindful Attention and Awareness Scale, and stress was assessed using the Perceived Stress Scale. Paired t‐tests and Wilcoxon signed rank test were used to compare outcomes pre‐ and post‐intervention. The analytic sample included 10 postmenopausal breast cancer survivors in remission with a BMI of ≥ 25 kg/m2 who completed the intervention. Mean age was 64.4 ± 6.0 years, 90.0% were non‐Hispanic white, 50.0% were married, and 50.0% had an annual household income of more than $80,000. All participants significantly lost weight (mean weight change: −0.8 ± 0.8 kg; p= 0.015). There was a trend towards increased mindfulness (mean change= 8.4% ± 0.5; p=0.090); but perceived stress did not change over the course of the intervention. At baseline and follow‐up, participants underreported energy consumption (1,237.7 ± 304.2 and 1,094.0 ± 319.4 kcal/ day, respectively), marking no significant change in caloric intake post‐intervention. Mean fat and saturated fat intake at baseline were 40.7 ± 3.8% and 13.8 ± 1.9% of daily energy, respectively. Participants reduced overall fat intake by −10.6 + 7.1 grams/ per day (p=0.002), and saturated fat by −3.56 ± 3.0 grams/ day (p=0.008) without significantly changing protein or carbohydrate intake. In addition, participants reduced intake of sweets by 2.5 ± 1.9% of daily energy (p=0.003). Despite not meeting current dietary recommendations, intake of fruits, vegetables, and whole grains were not altered. Findings of this study suggest that a mindful eating intervention may lead to improvements in fat, saturated fat, and sweets intake, but not other lifestyle factors, in overweight and obese postmenopausal breast cancer survivors. Larger, more adequately powered studies are needed to confirm the findings and examine effects if the intervention is carried over long‐term.Support or Funding InformationThe study was funded through the University of Georgia Clinical and Translational Research Unit seed grant.