Can a mariied man be charged with rape of his wife in maryland?

Yes, a man can be prosecuted for sexual offenses against his spouse in Maryland. Below is a part of the statute that applies. The referenced statute numbers are listed at the end of the response. Forcible rape is covered under 3-318 ( 2)

§ 3-301-3-324 Sexual Crimes
§ 3-318. Spousal defense.

(a) In general.- Except as provided in subsections (b) and (c) of this section, a person may not be prosecuted under § 3-303, § 3-304, § 3-307, or § 3-308 of this subtitle for a crime against a victim who was the person's legal spouse at the time of the alleged rape or sexual offense.

(b) Separation or use of force.- A person may be prosecuted under § 3-303(a), § 3-304(a)(1), or § 3-307(a)(1) of this subtitle for a crime against the person's legal spouse if:

(1) at the time of the alleged crime the person and the person's legal spouse have lived apart, without cohabitation and without interruption:

(i) under a written separation agreement executed by the person and the spouse; or

(ii) for at least 3 months immediately before the alleged rape or sexual offense; or

(2) the person in committing the crime uses force or threat of force and the act is without the consent of the spouse.

(c) Limited divorce.- A person may be prosecuted under § 3-303, § 3-304, § 3-307, or § 3-308 of this subtitle for a crime against the person's legal spouse if at the time of the alleged crime the person and the spouse live apart, without cohabitation and without interruption, under a decree of limited divorce.

3-303 Rape in the first degree
3-304 Rape in the second degree
3-305 Sexual offense in the first degree
3-306 Sexual offense in the second degree
3-307 Sexual offense in the third degree
3-308 Sexual offense in the fourth degree
An. Code 1957, art. 27, § 464D; 2002, ch. 26, § 2; ch. 266, § 1; ch. 278, § 1; 2004, ch. 524.]