Biochemical parameters participation in systemic inflammatory response syndrome (SIRS) development at tuberculosis/HIV co-infection has not been carefully studied by now and severity of endogenous intoxication, as well as its influence on the disease occur. Aim. To determine the intensity of endogenous intoxication in tuberculosis/HIV co-infected patients with first diagnosed pulmonary tuberculosis (FDTB/HIV), depending on the severity of the disease. Materials and methods. 54 patients with FDTB/HIV were examined and divided into 3 groups. The 1st group included 15 patients without SIRS, with local tuberculosis, without massive bacterial excretion, with the number of CD4(+)-cells more than 200 in 1 ml, or if there was the only one of the next signs (disseminative destructive tuberculosis, massive bacterial excretion, the number of CD4(+)-cells less than 200 in 1 ml). The 2nd group included 13 patients who had more than one sign. The 3rd group consisted of 26 patients with SIRS. SIRS was diagnosed by R. Bone et al. (1992). As a markers of endogenous intoxication C-reactive protein (CRP), rheumatoid factor (RF), fibrin, seromucoid by standard methods; alpha 1-antitrypsin (alpha 1-AT) - by immunoassay kit Immundiagnostik, Germany; protein fractions were determined by electrophoresis; intermediate mass molecules (IMM) - by B. Halliwell method (1999) were measured. Results. In FDTB/HIV patients seromucoid, fibrin, alpha 1-AT, gamma-globulins and IMM levels were increased; albumin levels and albumin-globulin ratio were reduced independently of the process severity. The levels of CRP and RF were also increased if disease was severer. Dysproteinemia is compounded in the presence of SIRS and IMM levels 2-fold increase compared to control. Conclusion. This indicates that the levels of acute inflammation phase marks, protein fractions and IMM are dependent not only on the presence of pathogens in the organism, but also on the disease severity.