Objective To investigate the roles of ultrasound-guided resection margin marking with dyes in the breast-conserving surgery for early breast cancer.Methods A total of 126 patients with stage Ⅰ and Ⅱ breast cancer treated in our hospital from January 2016 to May 2018 were selected and divided into control group and observation group. The control group was treated with conventional surgery, while the surgery in the observation group was facilitated by ultrasound-guided resection margin marking with dyes in advance. Complete tumor resections were performed according to the guidelines for breast-conserving surgery and the patients were followed up for 3 years. The rate of positive surgical margin, postoperative quality of life, mental health status, overall survival, disease-free survival, and the incidence of postoperative complications between the two groups were compared.Results The differences in scores of mental health, bodily pain, physical functioning, social functioning and general health before and after operation in the observation group were greater than those in the control group (P < 0.05). Besides, the differences in Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) scores before and after operation in the observation group were also greater than those in the control group (P < 0.05). The 1-year progression-free survival rate was not different between the groups (P > 0.05). However, the 3-year progression-free survival rate was higher, and the recurrence rate was lower in the observation group compared with the control group (P < 0.05). In addition, the rate of negative margins in the observation group was higher than that in the control group (P < 0.05).Conclusions The breast-conserving surgery for early breast cancer, facilitated by ultrasound-guided resection margin marking with dyes, improves the quality of life and the mental health status of patients, and affects the overall survival rate and progression-free survival rate.