The present study was devoted to evaluate the immunogenic potency of three different types of inactivated freeze dried vaccines of African Horse Sickness (AHSV). Each of the three vaccines was comprised of the three serotypes of AHSV (6, 7 and 8) but with a titre of 7.5, 6.5 and 7.5 log 10 TCDsd ml, respectively. The viruses were inactivated separately at 37°C by addition of binary ethyleneimine (BEI) at a final concentration of 0.004 m for 24 hours. The study was conducted on six adult susceptible horses which were divided into 3 groups (2 horses/ group). The first group (a) was inoculated intramuscularly (I/M) with the first type of vaccine combined with a purified tetanus toxoid (100 LF/3 ml) freeze dried vaccine, reconstituted in DEAE-dextran (100 mg/ml) solution. The second group (B) was inoculated I/M with the second type after reconstitution in DEAE-dextran solution. The third group (C) was inoculated subcutaneously with the third type after reconstitution in sterile saline solution. The immune response of the horses was evaluated using serum neutralization test (SNT) and complement fixation test (CFT). The third type was weak antigenically and unapplicable inducing a low and short seroconversion antibody response after primary and booster doses. Both the first and second type induced a rapid and high seroconversion after boostering and re-vaccination.