A Mendelsohn triple system, MTS(v)=(X,B), is called self-converse if it and its converse (X,B−1) are isomorphic, where B−1={⟨z,y,x⟩;⟨x,y,z⟩∈B}. In this paper, the existence spectrum of self-converse MTS(v) is given, which is v≡0 or 1(mod3) and v≠6.