Abstract. The purpose of the research is to develop a comprehensive assessment system with new indicators of feed behavior and feed conversion in Duroc pigs based on a selection index. Research methods. The Herdsman database was used, which includes the processing of data on fattening characteristics and feeding behavior of 764 heads of Duroc pigs that have passed test fattening at automatic feeding stations. 13 indicators were evaluated, of which 7 indicators of feeding behavior and 6 – fattening characteristics. The evaluation of breeding value animals according to studied traits was carried out using the BLUP Animal Model methodology. Results. When determining the weight coefficients of final index equation, which included all the studied traits, we relied on the chosen principle, according to which 50 % was given to weight coefficients of feeding behavior traits and 50 % to the weights of the fattening indicators. Also, in accordance with this principle, in feeding behavior indicators, 25 % was allocated for feed conversion, and the same amount in fattening indicators – for the average daily weight gain. The obtained values of the coefficients presented the general structure of the selection index: Itotal = 0.5I1 + 0.5I2 = 0.0241 (TPD) + 0.0439 (ADFI) – 0.0376 (NVD) – 0.0322 (TPV) – 0.0074 (FR) + 0.0376 (FPV) – 0.5343 (FCR) + 0.0531 (Age1) + 0.0778 (Age0) + 0.1217 (BW1) + 0.1027 (BW0) + 0.0331 (BWG) + 0.4557 (ADG). The results obtained showed the difference between the minimum and maximum index, which was 76 sigma points. Also, according to distribution according the categories of RBV (relative breeding value) among 14 pigs with an index greater than 120 units, 30.8 % have the category “unconditional improver” and 25.8 % – the category “improver”. Scientific novelty. These results show the direct impact of feeding behavior and feed conversion on the refinement of animal’s genetic potential, which will improve the system of selection and genomic evaluation of animals.