The invention provides a cathode active material that includes: a particle containing a cathode material capable of absorbing and releasing an electrode reactive material; and a film that is disposed at least partially to the particle and contains a metal salt represented by a formula (1). (R1 represents a (a1+b1+c1) valent group and M1 represents a metallic element. a1, d1, e1 and n each represent an integer of 1 or more and b1 and c1 each represent an integer of 0 or more. However, b1 and c1 satisfy (b1+c1)≧1.), a cathode therewith and a non-aqueous electrolyte secondary battery.