Objective To evaluate the effects of electro-acupuncture (EA) and hormone therapy (HT) on vasomotor symptoms in women with a history of breast cancer.Methods Forty-five women were randomized to EA (n = 27) for 12 weeks or HT (n = 18) for 24 months. The number of and distress caused by hot flushes were registered daily before, during and up to 24 months after start of treatment.Results In 19 women who completed 12 weeks of EA, the median number of hot flushes/24 h decreased from 9.6 (interquartile range (IQR) 6.6-9.9) at baseline to 4.3 (IQR 1.0-7.1) at 12 weeks of treatment (p < 0.001). At 12 months after start of treatment, 14 women with only the initial 12 weeks of EA had a median number of flushes/24 h of 4.9 (IQR 1.8-7.3), and at 24 months seven women with no other treatment than EA had 2.1 (IQR 1.6-2.8) flushes/24 h. Another five women had a decreased number of flushes after having additional EA. The 18 women with HT had a baseline median number of flushes/24 h of 6.6 (IQR 4.0-8.9), and 0.0 (IQR 0.0-1.6; p = 0.001) at 12 weeks.Conclusion Electro-acupuncture is a possible treatment of vasomotor symptoms for women with breast cancer and should be further studied for this group of women.