Roman Catholic Archbishop Eugene A. Marino, the nation's highest-ranking black Catholic priest, resigned yesterday from his post in Atlanta citing mental and physical health problems.

"I need an extended period of spiritual renewal, psychological therapy and medical supervision," Marino said in a brief statement delivered by Atlanta archdiocesan officials. "It is my hope that I may, in God's good time, be able to devote all my energies to the service of the church in some less demanding capacity."

Marino, who underwent treatment for alcoholism 12 years ago, would not elaborate on the reasons for his departure, according to an archdiocesan spokesman. Pope John Paul II named the Most Rev. James P. Lyke, a black auxiliary bishop from Cleveland, to run the diocese while another archbishop is found.

Marino, 56, has been on leave at a retreat house in New York since May and his absence has been the source of speculation among Catholics in Atlanta and Washington, where he served as auxiliary bishop for 14 years.

When Marino went on leave, his spokesman, the Rev. Peter Dora, said it was due to stress and physical ailments, including heart trouble and high blood pressure. Dora noted at the time that Marino had weathered several controversies during his tenure with the church.

As former auxiliary bishop to Cardinal James A. Hickey in Washington, Marino attempted to mediate between the cardinal and the Rev. George A. Stallings Jr., a maverick black priest who started his own congregation and took the title of bishop in defiance of church hierarchy.

When Marino went to Atlanta two years ago, he inherited the case of a visiting British priest accused of molesting four altar boys in a Stone Mountain, Ga., church. The priest pleaded guilty to the charges in May.

One priest who knows Marino well wondered whether his colleague enjoyed the support in Atlanta that he had in Washington. This priest said Marino regularly attended Alcoholics Anonymous in Washington and that his schedule in Atlanta prevented him from doing the same there.

Another priest said Marino, the country's first black archbishop, had a schedule in Atlanta "that would knock your socks off. I stayed with him in January," this priest said, "and he called me at 7:30 a.m. from his car phone, on the way to another meeting, to say goodbye." This priest said he saw no sign that Marino was abusing alcohol. Marino was jogging regularly, he said, and smoked only one cigarette a day, at bedtime.

While bishops have been known to take leaves of absence for reasons of stress and fatigue, resignations are extremely rare. One Washington priest said some black Catholics have wondered whether Marino was forced from his post for racial reasons, but that rumor was denied vigorously yesterday by those who know Marino.

Also, the appointment of Lyke, a well-respected theologian, to run the Atlanta diocese as apostolic administrator minimizes such criticism.

"Bishop Lyke is an excellent choice," said the Most Rev. Joseph A. Francis, a senior black bishop from Newark. "Many of us were saddened by the fact that another African-American might not be appointed to Atlanta. . . . The odds are 90 to 1 that Lyke will be the next archbishop."