Mirabilis jalapa L. is a gardening plant which growth easily planted because their beautiful color and flowerâ€™s ornaments. The aims of the research were to find out the variation of isozyme band of peroxidase (PER) and their close relationship of M. jalapa cultivated based on their different flowerâ€™s color. The method used in this study was polyacrilamide gel electrophoresis. The collecting data were analyzed using calculation of association coefficient (Gowerâ€™s coefficient) with cluster analysis used for similarities of their arithmetic. The results showed that in M. jalapa were found 21 variation of isozyme bands of peroxidase (PER) from 8 Rf of 0.04; 0.08; 0.20; 0.28; 0.36; 0.48; 0,60; and 0.64. M. jalapa with white and red nodes flowerâ€™s (BIN) and white and red line flowerâ€™s (GAR) have the nearest genetic relationship with similarity index of 0.76. M. jalapa with white and red nodes flowerâ€™s (BIN) and white and red line flowerâ€™s (GAR) joined with red flowerâ€™s (MER) on 0.73 of similarity index then joined with white flowerâ€™s (PUT) on 0.64 of similarity index and yellow flowerâ€™s (KUN) on 0.49 of similarity index. At least, M. jalapa with orange flowerâ€™s (ORA) joined with M. jalapa cultivars on 0.41 of similarity index.