Abstract: Lithium ion battery anode materials research is in full swing, has been actually applied to lithium ion battery anode materials are basically natural graphite, artificial graphite, other types of anode materials including hard carbon/soft carbon, alloy anode, lithium titanate, etc., manganese oxide to do the negative reports are not deep enough. Therefore, in this paper, manganese sesquioxide is used as the negative electrode material to study the physicochemical properties and electrochemical properties of the negative electrode. The results show that when the mass ratio of Mn2O3, acetylene black and PVDF is 7:2:1 at 550℃, the specific capacity has the best performance with the number of cycles. The initial discharge specific capacity is 978.7 mAh·g-1, and after 200 cycles, the discharge specific capacity is 532.1 mAh·g-1. The initial charging capacity is 938.9 mAh·g-1. With the extension of roasting time, the content of Mn2O3 crystal phase increases gradually, the grain size increases gradually, and the change of electrochemical properties is not obvious after roasting for 6 h. When the roasting time is 8 h and the roasting temperature is 700℃, the prepared Mn2O3 has better physicochemical and electrochemical properties, and its crystal phase content is high, the grain size is large and the crystallinity is high. The particle length is about 700 nm rod shape, the particle gap is large and the size is uniform. The initial discharge capacity is 1630.7 mAh·g-1, and after 200 cycles, the discharge capacity is 712.1 mAh·g-1.