Background: The clinical and morphological characterization of the subserous gallbladder carcinomas is controversial. Aim: To study the prognostic importance of DNA content of subserous gallbladder carcinoma. Material and methods: We studied 104 females aged 60±12 years old and 16 men aged 70±13 years old. In all of them diagnosis was established after mapping of cholecystectomy sample and had a complete clinical follow up. DNA content was measured by flow cytometry. Results: All tumors were adenocarcinoma, and only 16% were well differentiated. Aneuploidy was observed in 29 cases (26%) with DNA index fluctuating between 1.1 and 1.8. Lymphatic vessel tumor involvement was present in 16 of 22 cases with aneuploidy and in 22 of 46 diploid tumors (p= 0.05). Eighty nine percent of aneuploid tumors were detected macroscopically and 11% were unapparent. Five years survival was non significantly better among patients with diploid tumors than in patients with aneuploid tumors (45 and 28%, respectively, p= 0.2). The histological differentiation was the only variable significantly associated with survival. Conclusions: Aneuploidy is present in 26% of subserous gallbladder carcinoma. It is not related with any of the morphological or clinical variables studied in this series of patients (Rev Méd Chile 2004; 132: 794-800)