The serovars evolution of 3340 Salmonella strains isolated from 1986 to 1990 in Algeria have been studied. Among Salmonella responsible for typhoid-paratyphoid fevers, 98% are S. typhi; the prevalence of this serovar is observed every year. Among the other Salmonella, 50 different serovars have been isolated from 1986 to 1990. The predominant serovars change every year but 98% out of the total belong to 8 groups of Kauffmann White scheme; the most frequent are: groups O: 6, 7-O: 8-O: 4 and O: 9.