The State Department yesterday made public 11 pages of nonclassified information whose "cumulative weight" was cited by the department as proof that Nicaragua and Cuba are supplying and directing the leftist guerrillas in El Salvador.

The department, however, did not include any of the classified intelligence material that U.S. officials say was the basis for the secretary of state's contention that the United States has "overwhelming and irrefutable" evidence of outside command and control over the guerrillas.

Instead, department spokesman Dean Fischer said: "We cannot and will not make this intelligence available publicly. Were it to be released, the United States government would lose access to critical information and might well risk the lives of some brave people who believe it is important that the government of the United States know what is going on."

He added, "A government that does not keep secrets does not receive them."

As a result, the information released yesterday consisted largely of assertions that, in most cases, contained no backup details about how it was obtained and no gauge for evaluating its reliability or authenticity.

Some of the material was new. It contained the names of Nicaraguan ships and the location of airfields in Nicaragua allegedly used in smuggling arms into El Salvador, and it also described a number of incidents in recent months that the department cites as evidence of these arms turning up in the hands of guerrillas in El Salvador and Guatemala.

The rest was a repeat of information originally contained in the "white paper" on Nicaraguan involvement made public by the department a year ago, or of material that has been described in testimony before Congress by such officials as Secretary of State Alexander M. Haig Jr. and Thomas O. Enders, assistant secretary for inter-American affairs.

"The purpose of this paper is thus not to produce new revelations, but to describe the general pattern of outside support for El Salvador's guerrillas," Fischer said.

But it did not seem likely that the document will prove sufficient to still the demands for proof from critics of President Reagan's Central American policies since Haig made his charges of "overwhelming and irrefutable" evidence to the House Foreign Affairs Committee on March 3.

In an attempt to answer the critics, the administration has countered by holding briefings on its sensitive intelligence for select groups in Congress and for prominent former officials. Two weeks ago, it also invited reporters to an intelligence briefing on aerial reconnaissance photographs that it said proved a major military buildup in Nicaragua.

However, the controversy has continued. In part, it was fueled by the backfiring of the administration-arranged interview on March 12 with a 19-year-old Nicaraguan guerrilla captured last year in El Salvador. Instead of backing up the U.S. charges as expected, the captive said his earlier confessions had been obtained through threats.

To an even greater degree, the administration's problem has stemmed from inability to reconcile the need to give information to a public that has become increasingly skeptical about accepting the word of intelligence officials at face value and the resistance of the intelligence community that is concerned about endangering its sources.

It is an open secret that much of the intelligence on which the administration has based its judgments comes from intercepts of radio communications between Nicaragua and El Salvador. While that can be ascertained easily by reading the American press, the intelligence community, up to now, has prevailed in its insistence that a high degree of secrecy be maintained about the nature and source of the information.

That practice was maintained in the disclosures made yesterday. The documents included a description of the organization and key personnel of the leftist forces fighting the U.S.-backed Salvadoran government and a list of comments from members of Congress and former officials who saw some of the classified information and pronounced it convincing.

But the main part was devoted to "Cuban and Nicaraguan Support for the Salvadoran Insurgency." Among its highlights were these charges:

* Beginning last December, Cuban President Fidel Castro ordered a boost in arms shipments to El Salvador in an attempt to disrupt the elections scheduled to take place there next Sunday, and in the ensuing three months, these shipments have reached "unprecedented peaks."

* Since 1980, Salvadoran guerrillas have been trained in Nicaragua and have traveled between Managua and Havana on a daily air shuttle whose passenger load is so heavy that "a ticketing system is now required."

* Last April and July, Guatemalan forces in Guatemala City captured caches of guerrilla weapons, including some American M-16AR-15s originally shipped to U.S. units during the Vietnam war. Some of the vehicles captured with the weapons bore recent customs markings from Nicaragua.

* Three Nicaraguan ships--the Monimbo, the Aracely and the Nicarao--frequently transport arms and ammunition from Cuba to Nicaragua, where they remain stockpiled until arrangements are made for their transfer to El Salvador.

* The Unified Revolutionary Directorate (DRU) of the Salvadoran guerrilla groups has its command headquarters near Managua and guides planning and operations within El Salvador with "Cuban and Nicaraguan officers involved in command and control."

* Santo Salome Morales, a Salvadoran guerrilla who defected to Honduras last September, said he and 12 others had gone from El Salvador to Nicaragua in May, 1980, and from there, "They proceeded to Cuba where they received extensive military training, together with over 900 Salvadorans."

* The Papalonal Airfield, a commercially inaccessible airstrip in an area 23 miles from Managua, was improved and lengthened and used for a time to fly cargo planes loaded with weapons into El Salvador.