We have investigated the serum level of selected hematopoietic cytokines, such as interleukin 3, granulocyte-macrophage--colony stimulating factor (GM-CSF), granulocyte--colony stimulating factor (G-CSF) and macrophage--colony stimulating factor (M-CSF) in colorectal cancer patients. Also correlations between their concentrations and stages were made. The study was done on group consisted of 30 diagnosed colorectal cancer patients. The used classification of stage of the tumor was described by Dukes. The results were compared with control group consisted of 20 healthy persons. The examined factors were assayed by ELISA method. In colorectal cancer patients the serum levels of IL-3, GM-CSF and M-CSF were increased in comparison with the control group. The differences between cytokines concentrations in control group and colorectal cancer patients were statistically significant for GM-CSF and M-CSF. The serum levels of cytokines were higher in more advanced tumor stage. This results permit for further study on usefulness of these cytokines as a markers for colorectal cancer.