Rebellious Salvadoran Army Lt. Col. Sigifredo Ochoa Perez declared in his stronghold here today that fellow officers have guaranteed him they will not attack and have offered "moral support" for his two-day-old mutiny against the U.S.-backed defense minister.

At a rally in the tree-shaded town square, Ochoa told about 500 residents that he therefore is prepared to hold out "indefinitely" in his demand that Defense Minister Jose Guillermo Garcia resign. Ochoa balked after Garcia ordered him from his command here in Cabanas province to a post abroad.

Gen. Garcia met for the second straight day with his top officers at the high command in San Salvador, the capital, 45 miles southwest of Sensuntepeque. He took no steps to end Ochoa's revolt by force, but at the same time none of the 20,000-man Army's other officers joined Ochoa publicly in the demand for Garcia's resignation.

As a result, the crisis settled into a stand-off between Ochoa, isolated since Thursday night with his brigade and the population of this little hill town, and Garcia, huddled in his headquarters in the capital with the country's military leadership apparently unwilling to spill blood to discipline Ochoa.

In brief remarks to two American reporters this afternoon in San Salvador, Garcia portrayed himself as the patron of moves this country has made toward democracy and Ochoa as a ruthless, insubordinate officer bent on personal gain, Washington Post correspondent Christopher Dickey reported from San Salvador.

"Mr. Ochoa forgot he is a soldier and that soldiers obey orders," Garcia said as he prepared to leave the Defense Ministry at the wheel of a beat-up, bulletproof American sedan. "This is a constitutional regime. We have fostered a democratic scheme of things, and this is not the time for opportunistic military officers to obscure the efforts of a people and of an institution which, under my command, has initiated the democratization of El Salvador."

The confrontation brought into the open a serious split in the U.S.-advised Army. Despite denials by Ochoa, it seemed likely to diminish the military's effectiveness in the three-year war against guerrillas of the leftist Farabundo Marti Liberation Front, a conflict that has become a keystone in the Reagan administration's efforts to support friendly governments in Central America.

The rebellion also appeared particularly painful for the 55 U.S. military advisers stationed here as part of a military aid program that has poured in more than $125 million during the past two years. In keeping with policy, the advisers made no comment on Ochoa's mutiny. In the past, however, they repeatedly have singled him out as an example of what the Salvadoran officer corps should be like.

Ochoa, speaking to cheering townspeople from a circular bandstand under palm trees, referred to a political dispute that has been agitating El Salvador's politics and military affairs for several months. He said Garcia, in ordering him Thursday to Uruguay as military attache, accused him of political activity in connection with the National Alliance Party headed by former major Roberto D'Aubuisson, president of the Constituent Assembly and the country's foremost leader of the extreme right.

Ochoa denied the charge and what he called other "unjust accusations" while he described the attache post as "exile."

D'Aubuisson "is a friend, a compatriot, but I do not belong to any party," he added. "I am not political. I am a soldier."

His mention of Garcia's charge underlined the rivalry of D'Aubuisson and Garcia and recalled Ochoa's and D'Aubuisson's links through a network of military-school graduates from the early 1960s.

"There are still military men like him [Ochoa] who are corrupted by ambition and servility," Garcia said in San Salvador. "The tone we have set is impartial and we absolutely have not had political commitments with anyone." Such commitments, Garcia said, have been the motive for Ochoa's "grave error."

"Mr. Ochoa is animated by his spirit of ambition and it makes no difference to him that he endangers the future of the people," he added. Asked if "servility" and "ambition" characterized Ochoa's relations with D'Aubuisson, Garcia simply grinned.

Garcia's attempt to send Ochoa off to Uruguay--and Ochoa's refusal to go--appeared related to a struggle for influence already marked by charges from D'Aubuisson that Garcia has been too soft in pursuing the leftist guerrillas. The dispute also indirectly involves the United States, with Garcia clearly the favorite of U.S. diplomats here and D'Aubuisson's followers denouncing the extent of U.S. influence over interim President Alvaro Magana and Garcia.

D'Aubuisson and his party have been silent on Ochoa's mutiny, however, as has U.S. Ambassador Deane L. Hinton and his staff.

Ochoa said he had had no contacts with the U.S. Embassy. But in speaking with American reporters, he stressed that his rebellion was not a threat to the democratic system the United States is encouraging in El Salvador or to the stability of the country in the 10th month of Magana's elected government.

"Our struggle is against Garcia," he declared, adding later: "No, I don't think we are breaking the morale of the Army. On the contrary, I think we are bringing the Army together. The one breaking the morale of the Army is Garcia."

In a communique issued earlier, Ochoa demanded that Garcia resign and that Magana run the Army "through the armed forces high command," apparently pending nomination of another defense minister. Garcia has held the post for three years under as many governments.

Despite the lack of public statements from other officers, Ochoa told townspeople here he has obtained support, declaring: "I have received telephone calls from colleagues in the armed forces who are with me, who are with us. They have assured me that we will not be attacked."

While Army troops blocked the route into the province, journalists were allowed through the roadblock.

The crowd, milling about in warm morning sun, cheered its approval of Ochoa's words. Some supporters held crude placards with slogans endorsing the mutiny, waving them in front of their straw cowboy hats. As the rally went on, Army trucks were seen driving in from the countryside with peasants to swell the audience.

"I don't want to go to Uruguay," Ochoa said, crisp in pressed fatigues, Ray-Ban sunglasses and a camouflage beret cocked to the right. "I want to stay here with you."