Ohio Rev. Code § 3105.01: Divorce causes.

The court of common pleas may grant divorces for the following causes:

(A) Either party had a husband or wife living at the time of the marriage from which the divorce is sought;

(B) Willful absence of the adverse party for one year;

(C) Adultery;

(D) Extreme cruelty;

(E) Fraudulent contract;

(F) Any gross neglect of duty;

(G) Habitual drunkenness;

(H) Imprisonment of the adverse party in a state or federal correctional institution at the time of filing the complaint;

(I) Procurement of a divorce outside this state, by a husband or wife, by virtue of which the party who procured it is released from the obligations of the marriage, while those obligations remain binding upon the other party;

(J) On the application of either party, when husband and wife have, without interruption for one year, lived separate and apart without cohabitation;

(K) Incompatibility, unless denied by either party.

A plea of res judicata or of recrimination with respect to any provision of this section does not bar either party from obtaining a divorce on this ground.