Expression of matrix metalloproteinases 2 and 9 was studied in primary tumors and their metastases in patients with colorectal cancer. The correlation of immunoreactivity with clinical morphological signs, prognosis of the disease, and development of metastases in the liver was analyzed. The level of expression and distribution of markers in patients with colorectal cancer with metastases in the liver differed from that in control patients without metastases. Enhanced expression of matrix metalloproteinases 2 and 9 was detected in colorectal cancer patients with distant metastases. Increased expression of matrix metalloproteinase 9 was associated significantly with low histological differentiation of the tumor, deeper tumor invasion, and was more often observed in tumors of colorectal cancer patients with unfavorable prognosis. Thus, matrix metalloproteinase 9 is a valuable marker for clinical observation and prognosis in patients with this location of the tumor process.