Introduction. The novel emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global public health concern. The ongoing pandemic outbreak in Poland makes a great impact on the diagnosis and treatment of other conditions including cancer and non-neoplastic diseases such as other infectious diseases.Research design. This study aimed to analyze trends in morbidity of selected infectious diseases in Poland over the last 6 years and assess the impact of the SARS-CoV-2 (COVID-19) pandemic on the incidence of other infectious diseases from January 1, 2020, to December 31, 2020, compared to the same period in 2019. Results. No clear trend in the total number of cases of infectious diseases in Poland in the years 2015-2019 was observed. During the period from January 1, 2020 to December 31, 2020, a total of 1 273 155 SARS-CoV-2 infections were recorded in Poland; they represented the second most common disease entity in the analyzed period (after flu and suspected flu). At the same time, there was a decrease in morbidity for almost all disease entities for which at least one case had been reported in 2019. The mean hospitalization rate for COVID-19 amounted to 250.2 cases per 100 000 inhabitants. This article is available in open access under Creative Common Attribution-Non-Commercial-No Derivatives 4.0 International (CC BY-NC-ND 4.0) license, allowing to download articles and share them with others as long as they credit the authors and the publisher, but without permission to change them in any way or use them commercially.