Abstract: Aim: was to develop a score scale for the prediction of complete tumor necrosis to assess the potential effectiveness of radiofrequency ablation of colorectal cancer focals in liver, on the base of results of the use of radiological diagnostic methods. Materials and methods: a comparative analysis of results of radiological diagnosis of solitary colorectal cancer metastases in liver was carried out in 51 patients, depending on their characteristics before and at different times after radiofrequency ablation (RFA). The survey and interventions were carried out between 2014 and 2020 in accordance with standards of treatment approved in Belarus. Ultrasound and CT with bolus contrast enhancement were used as radiation diagnostic methods. The initial morphological parameters of tumor focals were evaluated according to results of ultrasound examination. CT with bolus contrast was used to control the effectiveness of RFA (determining the frequency of complete tumor necrosis): on the day of discharge of patients from the hospital, after 1 month, and then - once every 3 months (quarterly) during the year. Results: the dependence of the effectiveness of RFA (frequency of complete tumor necrosis) on initial characteristics of solitary focals of colorectal cancer in liver was revealed and confirmed by results of a comparative statistical analysis. On the basis of obtained data, a score scale for predicting the effectiveness of RFA was developed and validated. The sensitivity of the new technique was 80,0%; specificity - 82,9%. Conclusion: for the first time, a scale for the prediction of complete tumor necrosis was developed to assess the potential effectiveness of radiofrequency ablation of solitary colorectal cancer focals in liver. 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