To observe the clinical efficacy of basal metabolic weight loss method combined with kidney-nourishing and phlegm-resolving method in the treatment of overweight and obese polycystic ovary syndrome (PCOS). Methods From April 2022 to April 2023, 70 patients with overweight and obese polycystic ovary syndrome diagnosed and treated in our hospital were selected and divided into control group (n =35) and observation group (n =35). The control group was treated with basal metabolic weight loss method, and the observation group was treated with kidney-nourishing and phlegm-resolving method on the basis of the control group. The clinical efficacy, TCM clinical symptoms (oligomenorrhea, amenorrhea, acne, hirsutism) score, body weight, waist circumference, free testis and luteinizing hormone were compared between the two groups. Results In the observation group, the total effective rate of treatment was 94.29%, which was higher than 80.00% in the control group (P <0.05). The observation group had lower the scores of oligomenorrhea, amenorrhea, acne and hirsutism than those in the control group (P <0.05). After treatment, the body weight and waist circumference of the two groups were less than those before treatment, and those in the observation group were less than those in the control group (P <0.05). After treatment, the free testis and luteinizing hormone in the two groups were lower than those before treatment, and those in the observation group were lower than the control group (P <0.05). Conclusion For overweight and obese patients with polycystic ovary syndrome, basal metabolic weight loss combined with kidney-tonifying and phlegm-resolving therapy can improve the total effective rate, reduce TCM symptoms, reduce body weight and waist circumference, reduce the levels of free testis and luteinizing hormone.