The development of an inactivated combined vaccine against rhinopneumonia and horse strangles is presented. Acute toxicity, pyrogenicity and immunogenicity of the vaccine in laboratory animals have been studied. Preclinical trials of the vaccine were conducted on mongrel outbred mice and rabbits. Testing of the vaccine preparation on male rabbits showed its apyrogenicity. The immunogenicity of the viral component of the vaccine was tested on 10-14-day-old outbred mice with a body weight of 6-7 g. The vaccine was administered subcutaneously to the 1st group of mice (n = 8) 0.3 ml twice with an interval of 14 days. Mice of the 2nd group (n = 6) were used for negative and positive control. 14 days after the second immunization, a control intracerebral infection with an adapted strain of equine rhinopneumonia virus was carried out at a dose of 0.02 × 6.0 lgTSD 50 / ml. The immunogenic activity of the strangles composition of the vaccine was tested on mongrel white mice. The vaccine in a dose of 0.5 ml was administered subcutaneously to 10 white mice. After vaccination, 10 days later, infection with a lethal dose of strangles streptococcus was carried out in experimental and control groups of laboratory mice LD 50 , which amounted to 200 thousand microbial bodies in 1 ml. In the mice of the experimental group, body weight increased by 1.5 g during observation, in the control group – by 0.9 g. According to the results of pathomorphological and histological studies, no changes in the internal organs caused by the administration of intragastric drugs were detected. Preclinical testing showed the absence of acute toxicity, allergenic, pyrogenic properties and immunogenicity of the combined vaccine against rhinopneumonia and horse strangles. The combined vaccine protects against experimental infection with the rhinopneumonia virus by 75 %, with the causative agent of horse strangles by 80 %.