Dr. Leon T. Davis of Walter Reed Army Medical Center has become the military's first doctor to stage a sit-down srike.

He told The Washington Post yesterday that he is refusing to practice anymore to protest what he and hundreds of fellow doctors consider breaches in their contracts with the military.

The 30-year-old radiologist further contended that his case is symbolic of a crisis in military medicine, with inadequate medical care for service people "and sometimes malpractice" the result.

A recent Pentagon report rejects that charge, but does not show that only 23 percent of the military's doctors "are likely to stay in the service until retirement."

Before staging his sit-down, Davis organized a protest group of 630 military doctors who have filed suit in U.S. District Court here in an attempt to redress their grievances about pay and promotions.

After his sit-down, Army superiors put Davis under house arrest at the Walter Reed Inn across Georgia Avenue from the hospital and recommended that he be court-martialed for failing to obey orders to continue practicing either in Korea or Walter Reed.

Maj. Gen. George I. Baker, commander of Walter Reed, yesterday declined, through a spokesman, to discuss the case. But his letter of Oct. 5 recommending that Davis be punished for failing to obey orders rather than be allowed to resign describes his position.

"This conduct constitutes a possible deliberate attempt to subvert the basis of obligated military service by officers of the Army Medical Department and the United States Army," Baker said of Davis. "The charges, if proven, demand that Capt. Davis be justly punished and that others be deterred from following his example."

Davis countered that he would have compromised his argument if he had continued to practice after asserting that the Army contract with him was null and void because of the breaches.

The radiologist says that the Army has broken promises to provide him with modern medical equipment; pay him the military doctors' bonus of $9,000 a year after completing his residency; allow him to attend medical meetings and take 30 days a year vacation.

Davis obligated himself to serve as a military doctor for two years in exchange for the Army's paying for part of his medical school education under a program called the Health Professions Scholarship Program.

The promises he alleges were broken were made when he signed up, Davis said.

Through bureaucratic mixup, according to Davis and his lawyer, Stephen D. Keeffe, about 7,000 doctors who came into the military under that scholarship program will not get the $9,000 annual bonus they were promised. Physicians who joined the service via other routes will get the extra money, they said.

Keeffe has filed two separate class-action suits against the government on behalf of military doctors. The suits demand that the doctors be given the bonuses and promotions they were promised. No trial dates have been set.

Davis and Keeffe contended that there is a dangerous disillusionment spreading through the military medical corps, impelling doctors to quit in droves. This is leaving the military so short of physicians that service people do not get adequate medical care, they said.

"In some cases," said Davis, "the shortage is so severe that the result is malpractice."

Rep. Robin Beard (R-Tenn.), ranking minority member of a House Armed Services subcommittee investigating medical care in the military, said yesterday that the Davis sit-down and the doctors' suits "are symbolic of a growing sickness in military health care."

All told, there are 10,769 doctors in the military, counting interns and those completing residency requirements. The Health Professions Scholarship Program, now under challenge in the courts, is the military's main incentive program for attracting young doctors.

Davis said he joined because he was willing to exchange the higher salary he could make on the outside for the opportunity to use the latest equipment in military hospitals, where there would be a wide range of patients.

To his astonishment, said Davis, he discovered in reporting to Walter Reed that this most prestigious of military hospitals had such outdated diagnostic radiological equipment that patients often had to be examined again and again because of mechanical failures.

Doctors at military hospitals outside of Washington, Davis said, have complained to him that shortages of personnel and modern equipment are often "horrendous."

In a recent report prepared for the assistant secretary of defense for health affairs, the Pentagon said that "over 70 percent" of 3,000 military physicians who responded to a survey "believe that the quality of military medicine is equal to or better than the civilian sector."