Background: Lactation has a negative effect on female sexual function. Hormonal changes during lactation cause changes which might lead to dyspareunia, lack of libido, and anorgasmia. There are various pharmacological and non-pharmacological approaches to treat sexual dysfunction. While pharmacological treatment has multiple unwanted side effects, non-pharmacological therapies such as complementary medicine are a potential safer alternative. The aim of this study is to evaluate the effect of ear acupressure on sexual function of lactating women. Methods/design: This is a randomized clinical trial with a parallel sham control group. In this study, 76 lactating women between 6 months and 1 year after childbirth were referred to health care centers in Qazvin City and would be invited to participate. Participants will be divided into intervention (n = 38) and control (n = 38) groups using simple block randomization. Both intervention and sham control groups will be visited over 10 sessions within a 4-day interval. At each visit, the adhesives containing Vaccaria seed will be adhered for the intervention group, while non-latex-based adhesives with no Vaccaria seeds will be placed on the same ear acupoints for the sham control group. Selected ear acupoints include genitalia (two ear points), pelvic point, master shoulder, and posterior pituitary gland. The women will be asked to hold the seeds on their ears for 3 days and press each ear point three times a day for 20 s. After 3 days, they will be asked to remove the seeds from their ears and rest for 1 day. Sexual function as primary outcome in both groups will be assessed using the Female Sexual Function Index before and immediately after 1 and 2 months after the intervention. Also, Sexual Quality of Life as secondary outcome will be assessed using Sexual Quality of Life-Female (SQOL-F) before and 2 months after intervention. Data will be analyzed using repeated measure ANOVA at the significant level of 0.05. Discussion: This study is expected to support the impact of ear channel ear acupressure on sexual function in lactating women.