Abstract Introduction The aim of the study was to compare two methods of the sentinel lymph node biopsy (SLNB) procedure in bladder cancer (BC): we applied technetium radiocolloid (RadCol) detected by a gamma ray detection probe, and ICG detected by a near-infrared fluorescent (NIRF) camera. Material and methods The SLNB was performed on 50 patients using the technetium nannocolloid and the ICG, followed by a lymphadenectomy and a pathological examination. Results In the analyzed group of 47 patients (3 patients were excluded due to the lack of lymphatic drainage from the tumor) the SLNB was performed using the two methods. The ICG with a NIRF-guided camera detected all sentinel lymph nodes (SLNs) in 46 cases, whereas RadCol- in 45 cases. In 12/47 (25.6%) patients the ICG – fluorescent method revealed more SLNs than the RadCol. In 8 patients (17%) the SLNs revealed in the ICG fluorescence were metastatic. In 3 patients (6.4%) we found SLNs outside the standard lymphadenectomy template, but a histopathological examination showed they were negative for cancer. In 3 patients (6.4%) the SLNs detected by both methods were negative for cancer, but other resected lymph nodes revealed metastases. Conclusion Our study shows that SLNB procedure with the radiocolloid or the ICG is useful for the evaluation of lymph nodes in BC. The new ICG fluorescent technique with a NIRF camera system is safe, enables live view of the results of the procedure, and does not create additional costs. However, it highlights more lymph nodes than the radioactive method.