The study compares the oak pollen seasons in Bialystok, Bydgoszcz, Sosnowiec, Lublin, Olsztyn, Opole, Piotrkow Trybunalski, Szczecin, Warsaw, Wroclaw and Zielona Gora in 2019. The investigations were conducted using the volumetric method. The oak season started in all measurement sites between April 6th (Szczecin) and April 24th (Lublin and Piotrkow Trybunalski). The peak values of seasonal pollen count occurred between April 25th and May 2nd. The highest daily pollen count was recorded in Lublin (273 P/m3) and the lowest pollen count in Bialystok (23 P/m3). The highest annual totals were recorded in Lublin, Piotrkow Trybunalski and Warsaw. The most days with concentration equal to or above 16 P/m3, causing symptoms in many allergic patients, were recorded in Lublin and Warsaw. Days with concentration equal to or above 91 P/m3, which causes allergy of all sensitized patients, were the most frequent in Lublin, Piotrkow Trybunalski and Warsaw