This study investigated the prevalence of inclusion body hepatitis (IBH) infections during the past five years (2010-2014) in broiler chicken flocks in Poland. The diagnosis of IBH was based on anatomopathological investigations and histopathological analyzes. IBH was the most prevalent disease in broiler flocks in Poland (10.4%) during this time period, and occurred as a primary infection. The fewest cases of IBH occurred in the summer, suggesting that the temperature may have been a possible stressor that increased susceptibility to IBH. However, over the last 5 years the occurrence of clinical IBH cases in Poland has systematically decreased.