In this study, in vitro growth characteristics of fibroblasts of metacarpal region of horses and Caspian miniature horses were evaluated. Under general anesthesia and aseptic condition, A full thickness skin incision was created on the lateral aspect of mid-third of left metacarpal region of 4 mixed thoroughbred horses and 4 caspian miniature horses and 3 grams of subcutaneous tissue was harvested and placed in culture medium (RPMI-1640) in an incubator at 37°C (5%CO2). After growth of fibroblasts, count of cells was performed for 8 days and growth rates and percentage viability of fibroblasts were recorded. There were no significant differences in the growth rates and viability rate of fibroblasts between horses and caspian horses. It was therefore concluded that due to Genetic similarity between horses and caspian horses, growth characteristics of fibroblasts in these two groups are the same, but Further In vivo research is needed to identify the wound healing pattern in Caspian horses in compare with horses.