The aim of this study was to investigate the influence of suppository bases on aminophylline dissolution. The research material composed of 6 formulations of suppositories each containing 100 milligrams of aminophylline. Prepared batches were evaluated with regard to appearance, uniformity of dosage units, uniformity of content, disintegration and softening time (of lipohilic suppositories). All batches met pharmacopoeial requirements and underwent dissolution tests. Commercially available aminophylline suppositories underwent this test too. It was demonstrated that suppositories made on polyoxyethylene glycol base had the highest dissolution rate (88 percent in 2 hours). Dissolution rates for the others formulations were: 13 and 18 percent for cocoa butter base and cocoa butter with addition of Tween 80 respectively; 65 percent for Witepsol H-15 base, 7 and 14 percent for Witepsol H-15 with addition of 2 or 1 percent of aluminum tristearate, respectively. In confrontation dissolution rate for commercially available suppositories was 10 percent.