Fatigue is a significant problem in patients with bladder cancer treated by radical cystectomy. This pilot study evaluated fatigue and related variables during a treatment period. Four measurements were made, the first 1 month after the cystectomy, and the next three at an interval of about 3 months each (at 4 months, 7 months, and 10 months after the surgery). In addition to the author's questionnaire (sociodemographic variables and a question about the impact of the disease on the patient's life), the FACIT-F Fatigue (to measure fatigue), NCCN/FACT FBISI-18, version 2 (symptoms, general condition of the patient), HADS (depression, anxiety, and irritability) measures were used. In this study, 21 patients participated in all four measurement periods. The fatigue intensity increased significantly between the first and second measurements and gradually decreased between the third and fourth measurements.As the severity of fatigue increases, can be observed an increase in the sense of the impact of the disease on the patient's life in all except the first measurement.The study revealed statistically significant correlations between fatigue and experiencing symptoms of cancer and treatment at each stage of the study, with the strongest correlations in the second and fourth measurements regarding symptoms of cancer and a stronger correlation in the second compared to the first measurement regarding side effects. At each stage of measurement, the experience of dizziness, lack of appetite, feeling of being sick, and feeling of annoyance from treatment side effects were statistically significantly correlated with fatigue. The intensity of fatigue correlated with the feeling of experiencing difficulties in meeting the needs of the family due to the physical condition in the first measurement (Rho = 0.76), a sense of weakness (Rho = 0.92) and sleepiness (Rho = 0.72) in the second measurement, pain in the third (Rho = 0.77). The greatest number of correlates of fatigue were described in the fourth measurement (all symptoms of cancer and side effects except losing weight).Stress, anxiety, depression and irritability were correlated with fatigue at each of the stages of research except the first one (without differences between the correlation coefficients in the second, third and fourth measurements). Significantly lower levels of fatigue characterised patients who survived over 6 months after the end of the study compared to the first three measurements.