The effect of humic acid, which is an replace by a biostimulant on mitotic activity and chromosome behaviors in meristem cells of Hordeum vulgare L. germinated under different salt concentrations were investigated. In the parallel to increasing salt concentrations, mitotic index partly decreased and observed the higher number of chromosomal abnormalities as compared to control. Also, it was determined that the mitotic index of seeds pretreated with only humic acid increased by 30% according to control and by 42% of mitotic aberrations. Whereas, humic acid along with salt significantly inhibited to mitotic index with parallel to increasing salt concentrations. Moreover, the frequency of chromosomal aberrations in seeds germinated in humic acid and salty medium significantly decreased according to its own control. Humic acid revealed to a successful performance in ameliorating of the detrimental effect of salinity in the all concentrations studied. Humic acid application at 0.35 M salinity displayed perfectly successful by reaching to the same abnormality percentage of control.