The article reveals the relationship between the development of external enterocutaneous fistulas and variants of the genotype distribution of MMP-2 (C-1306 → T) and TIMP-2 (G303 → A) genes. Based on the received data personalized way of forecasting of the enterocutaneous fistulas is developed. The object of the study were 19 patients with enterocutaneous fistulas of anastomoses, who were treated at the State Institution "NIST named after O.O. Shalimov ". Laboratory, genetic and statistical studies were conducted. When analyzing the frequency of allelic polymorphism of the MMP-2 gene, it was found that in the experimental group with enterocutaneous fistulas, the frequency distribution of the polymorphism of the MMP-2 gene promoter, in general, corresponding to the control group for SS, CT, and TT variants. In the analysis of TIMP-2 inheritance models (G303 → A), in the control groups (n = 80) and the experimental group (n = 19) we were able to find statistically significant differences in the distribution of genotypes (p <0.05). Thus, the dominant homozygous GG variant was 1.58 times higher than the control values (p = 0.057). Heterozygous GA genotype in the experimental group was twice less common than in the control (21.1% vs. 40%).Carriers of homozygous AA genotype in the group with enterocutaneous fistulas were not detected, while a similar variant in the control occurred in 10% of cases.