Introduction and objective:
The health status of people at working age is one of the elements exerting an effect on the socio-economic development of a given population. The aim of the study was to assess the incidence of malignant cancers among population at working age in the Podlaskie Province during 1999–2017.

Material and methods:
Information from the National Cancer Register (NCR) was used to analyze and assess the incidence of malignant cancers among the inhabitants of the Podlaskie Province in the age group with the highest economic activity. Information concerning the incidence of malignant cancers in the group aged 20–64 in the Podlaskie Province during 1999–2017 was also included.

Results:
In 2017, in the Podlaskie Province, 837 new cases of malignant cancers were registered among males aged 20–64, which means an increase by nearly 15%, compared to 1999. In females, the number of new cases increased by almost 19%, from 789 cases in 1999 up to 936 in 2017. In the analyzed period, the value of the crude incidence rate (CR) in males also increased by 4.7%, whereas in females – by 18.6%. The age-standardized incidence rate (ASR) decreased by 18.3% in males and by 5% in females.

Conclusions:
During the analyzed period, in the Podlaskie Province, an increase was observed in the number and value of the crude cancer incidence rate in the age group 20–64. Among females at the age of the highest professional activity, both the level and the course of the trend of the actual incidence rate indicated a rapid increase in the risk of malignant cancer. A high morbidity due to malignant cancers in the group aged 20–64 is one of the greatest challenges for public health in Poland, and indicates an urgent need for undertaking planned measures to protect and improve the health of working people.