There is interest in growing peanut (Arachis hypogaea L.) for forage, but little is known about the nutritive value and forage quality. The objective of this study was to Determination chemical composition and in Situ degradation kinetics of peanut hay. Sample randomly collected and then shadedried. Chemical composition were measured according to the standard procedure. Dry matter digestibility determination by in situ methods. chemical composition including dry matter (DM), Organic matter (OM), crude ash (CA), ether extract (EE), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were estimated: 94/48, 89/23, 10/76, 2/20, 7/79, 41/21 and 28/14 respectively. The In situ DMD values for time incubation 3, 6, 12, 24, 48, 72, 96 h were estimated: 29/76, 32/55, 39/64, 45/89, 54/9, 63/01 and 70/5 respectively. It is noteworthy The DM disappearance of the peanut hay in the rumen increased with increasing incubation time. The value of in situ ruminal degradation cofficients of DM (a, b, c, a+b) and effective degradability of DM at outflow rate 0.02, 0.05 and 0.08 h -1 were estimated 28/60, 53/32, 0/0152, 81/92, 51/62, 41/03, 37/11 respectively. According to this experiments findings, it can be concluded that peanut hay have high nutritive value and therefore they can be used as alternative forage in ruminant nutrition.