The aim of this study was to evaluate, by means of ultrasound exam, acupuncture effects on uterine involution during the postpartum period in bitches with electroacupuncture. The phenomenon of eutocic uterine involution was studied in 16 bitches, randomly divided into two groups of eight animals each. Group 1 (G1) was treated with electric stimulation (electroacupuncture) of the needle at the points SP6, L3, Bai Hui, TB1, B23, B26, and group 2 (G2), the control group, received treatment in Sham points (placebo points), also with electrical stimuli. The monitoring of the phenomenon of uterine involution was performed by ultrasonography on days 0 (partum), 1, 3, 7 and 14 postpartum. We used SAS statistical analysis method, in order to compare the groups. The results of ultrasound examinations (mean and standard deviations in cm) for the period of observation were as follows: G1: 0.30 ± 0.01 (P), 2.08 ± 0.21 (LU), 4.13 ± 0.23 (DU) and G2: 0.31 ± 0.01 (P) 1.82 ± 0.09 (LU), 3.92 ± 0.11 (DU). We concluded that electroacupuncture affected uterine tone (lasting and uniform at the end of treatment). Electroacupuncture produces a positive tone in the uterus, aiding at the prevention of puerperal diseases.