Abstract : Wound examination is a critical issue in forensic practice. Determination of wound age and vitality is an essential issue in forensic pathology to evaluate accurately its causal relationship to death and forensic pathologists are always required to differentiate ante-mortem wounds from post-mortem damage. Moreover, when the wound is vital, it is necessary to determine how long before death it was sustained. The aim of this study was to estimate skin wound age and differentiate between ante-mortem and post-mortem wounds immunohistochemically using some tissue markers (TNF-α, CD45 and CD68) and histopathologically in rats. This study was conducted on 120 adult male albino rats which were selected randomly and divided into 4 groups: Group I (control group), ante-mortem wounds groups (II, III, IV, V& VI) at different time intervals (0.5h, 3h, 6h, 24h &48h) respectively, post-mortem wounds groups (VII, VIII, IX, X& XI) at different time intervals (0.5h, 3h, 6h, 24h &48h) respectively and putrefaction group (XII) obtained from the animal house of the Faculty of Medicine, Tanta University. Comparison between TNF-α, CD45 and CD68 for diagnosis of wounds age at 0.5, 3, 6, 24 and 48h illustrated that at 0.5h and 24 h, CD45 was the best marker for wound aging. While at 3h and 6h, TNF-α was the best diagnostic marker for wound age and regarding wounds aged 48h, CD68 was the best. TNF-α, CD45 and CD68 expressions in ante-mortem skin wounds were time dependent and significantly differed from post-mortem wounds. Where, CD45 was the best marker for dating of wounds at 0.5 and 24h. While at 3h and 6h, TNF-α was the best diagnostic marker for wound age and regarding wounds aged 48h, CD68 was the best.