A non-aqueous electrolyte secondary battery uses, as its positive electrode or negative electrode, an electrode containing an active material and a conductive agent, the active material being made of a mixture of a molybdenum dioxide and a lithium titanium oxide in a weight ratio (molybdenum dioxide: lithium titanium oxide) of from 90:10 to 50:50, and the conductive agent containing graphitized vapor grown carbon fiber and massive graphite. The massive graphite has an average particle size of 10 .mu.m or greater.