Praziquantel was blended into ground mouse feed at 35, 70, and 140 ppm in one replicate and at 140, 210, and 280 ppm in a second replicate. Mice naturally infected with Hymenolepis nana were provided this diet for 7 consecutive days. Reduction of Hymenolepis nana in mice receiving medicated feed when compared to mice receiving nonmedicated feed was 48.9, 73.2, and 87.1%, respectively in replicate 1, and 100% in all three groups in replicate 2. These data suggest that praziquantel blended into the feed at 140 ppm for 7 consecutive days will provide efficacious (87.1-100%) control of Hymenolepis nana in mice. Higher dosages may be necessary for complete elimination of this parasite.