Background. Ascites is a common clinical condition encountered by physicians in day-to-day practice. It is caused by various underlying diseases. Knowing the etiologies is vital because further investigations and definitive treatment largely rely on the specific disease entity considered. Objective. The aim of this study was to determine the epidemiology of causes of ascites and complications among patients with ascites from the medical department at the University of Gondar Hospital. Methods. Data on sociodemography, major symptoms, and signs, risk factors, past medical illnesses, and results of important investigations were collected using pretested questionnaires among all patients with ascites in the University of Gondar Hospital in a sample size of 52. Data were collected by well-trained physicians and analyzed by using SPSS 16. Results were depicted descriptively with measures of central tendency, dispersion, and using tables and graphs. Results. A total of 52 patients were included in this study from November 1, 2018 to March 30, 2019. Thirty (57.7%) of them were males and the majority (77%) of the participants were fifty years old or younger. The mean age was 43.8 (± 14). The majority (86.5%) of the participants were from a rural area. Thirty-eight (73%) patients take alcohol occasionally while 11(21.2%) patients take alcohol frequently or massively. Eight (15.4%) patients reported a history of multiple sexual partners. Herbal medicine use was reported by 28 patients (53.8%). Only 5 (9.6%) patients were overweight. Chronic liver disease (CLD) was the major cause of ascites in this study in 24 (46.2%) patients. The other main causes of ascites were heart failure from various causes (19.2%), tuberculosis and hepatosplenic schistosomiasis contributing to 11.5% each and chronic kidney disease (5.8%). Five (20.8%) CLD patients had spontaneous bacterial peritonitis as a complication. Five (20.8%) and 4 (16.7%) CLD patients had hepatocellular carcinoma and hepatic encephalopathy as complications, respectively. Nine (17.3%) patients had variceal bleeding; six of the patients were diagnosed to have CLD while the remaining patients were having hepatosplenic schistosomiasis. Conclusion. In conclusion, liver cirrhosis is the major cause of ascites in Gondar, Ethiopia, while chronic viral hepatitis infections (hepatitis B (HBV) and C (HCV) viruses) are the main causes of liver cirrhosis. The other major causes included heart failure, tuberculosis, and hepatosplenic schistosomiasis. It is wise to consider and give priority to these diseases whenever one is evaluating a patient with ascites.