Background: Despite a temporary decrease in the number of newly HIV infections in Poland in 2020, a return to the growing number of new infections was observed in 2021 in the surveillance. Objective: The aim of the study was to assess the epidemiological situation of newly HIV infections and AIDS cases and death among AIDS cases in Poland in 2021 in comparison to the changes in preceding years. Material and methods: Analysis of the epidemiological situation was based on reports of newly detected HIV cases and AIDS cases received from doctors and laboratories and the results of the annual survey of HIV testing conducted by laboratories throughout the country. A dataset on clients from Voluntary Testing and Counselling, coordinated by the National AIDS Center, which anonymously collects epidemiological and behaviour data on tested people was used. Results: In 2021 there were 1 367 HIV cases newly diagnosed in Poland (diagnosis rate 3.58 per 100,000), including 236 among non-Polish citizens. The number of HIV infections increased by 43.3% compared to the previous year and was higher by 3.8% compared to the median in 2015-2019 years. Similarly, among VCT clients, number of HIV increased by 45%, from 309 in 2020 to 448 in 2021 year. The total number of AIDS cases reported to surveillance was 62 (incidence 0.16 per 100,000). The HIV infection was most often detected in the age group 30-39 year (35.8%) and among men (82.1%). Among cases with known transmission route, 68.7% concerned among MSM. The percentage of AIDS cases diagnosed at the same time with HIV increased by more than 30 percent points (from 63.5% to 95.1% of all AIDS cases). Conclusions: In 2021 the number of newly detected HIV infections increased compared to the previous year, probably due to a reduction in restrictions related to the COVID-19 pandemic and increased in HIV testing rate.