The objectives of this study were to observe effect and  the effective dose of cinnamon (Cinnamomum burmanii) aqueous extract on pancreas structure of strain Balb-C mice (Mus musculus) diabetic after alloxan exposure. A total of 30 strains Balb-C mice (Mus musculus L.) were divided into 5 groups. Negative control group was not induced  by alloxan and a positive control group was induced alloxan 0,15 mg/g bw intraperitoneally for 9 days. The treatment group was divided into 3 groups was induced alloxan 0,15 mg/g bw and given an aqueous  extract of cinnamon at a dose of 0,73 mg/g bw; 1,09 mg/g bw and 1,45 mg/g bw orally for 7 days. Mice were dissected pancreas histhological taken using paraffin method and Haematoxylin-eosin (HE) stain. The result showed giving aqueous extract of cinnamon gave a strong effect in the repairing of pancreas structure after giving the alloxsan and the most effective aqueouse xtract of cinnamon with dose of 0,73 mg/g bb was able to repair the structure of mice's pancreas after giving the alloxan. Keywords: Cinnamon,  pancreas structur,diabetic mice