Introduction: Pulpitis Irreversible is a root canal inflammation that can be caused by Enterococcus faecalis. Root canal treatment can be done to eradicate pulp necrosis but in some cases bacteria may still persist. Immune respons- es that may happen during inflammation is the increasing expression of sitokin inflammation especially TNF-α. The acemannan as a bioactive polysaccharide component of Aloe Vera was known to be used in herbal medicine. It also can be used as anti inflammatory and anti-bacterial. Methods: This study used a sample of 22 Rattus norvegicus that had been induced by Enterococcus faecalis in the apical canal for 21 days. The research group was divided into six groups consisting of two control groups and 4 groups, each of which had the acemannan paste of 1 and 7 days, and also had the MTA of 1 and 7 days. After 1st and 7th day of paste application, the object was being sacrificed then made into a preparat and adding immunohistochemical staining afterwards, TNF-α was counted in every 5 field of views method using microscope. The data obtained was performed using a one-way ANOVA. Results: Based on the one-way ANOVA, obtained p <0.005 showed the difference of TNF-α numbers between the control group and the acemannan group has significantly different results, and the most degradation number of TNF-α occurs in the acemannan group. Conclusion: There was a significantly decreasing number of TNF-α after being given acemannan paste in Rattus norvegicus.