Atrophic scars are a frequent consequence of acne, with a negative esthetic and psychological influence. Treatment of atrophic acne scars includes different invasive methods. In our study, we used a noninvasive method with local application of 0.05% tretinoin gel by iontophoresis. In patients with a tendency towards exacerbation, we performed mild peeling with 5% trichloroacetic acid (TCA) solution 3-4 times during the treatment. Twenty-minute treatments were applied on 38 patients, 29 women and 9 men, during 3.5 months on average. Median age of patients was 21 years (range, 16-29). Clinical assessment included an assessment of scars, pore size, skin moisture, vascularization, and skin firmness and elasticity. As confirmed by photographs taken before and after therapy, the treatment proved to be clinically effective in decreasing acne scars and persistence of effects. Flattening of acne scars was observed in 79% of the patients. The results depended on duration of scars persistence as well as on a the type of scars. The best results were achieved with younger scars as well as with superficial and ice pick scars. Side effects involved a very mild retinoid dermatitis and more often acne exacerbation. The therapy was clinically effective and the patients accepted the treatment very easily. Local therapy of acne scars with tretinoin by iontophoresis can in some cases successfully replace invasive techniques, and could also be combined with those techniques.