Rep. Lester L. Wolff (D-N.Y.) yesterday charged that the Carter administration is more concerned with preserving good relations with the Burmese government than in cutting the supply of heroin from that Southeast Asia nation.

In the first of two days of hearings on ways to halt the flow of heroin into the United States from the Golden Triangle region of Burma, Thailand and Laos, Wolff suggested a plan for the United States, through an intermediary, to buy 250 tons of opium for $6 million a year for the next six years from the Burmese. The hearings are being hold by Wolff's Select Committee on Narcotics Abuse and Control.

But the proposal was rejected by Dr. Peter Bourne, a special assistant to President Carter and director of his Office of Drug Abuse Policy, and Robert B. Oakley, a deputy assistant secretary of state for East Asian and Pacific affairs, who testified at the hearing.

Wolff said that several warlords or "insurgents" from the Golden Triangle have offered to work with the United States to eradicate opium fields, which for centuries have been an integral part of the local economy there. He showed a film of committee staff aides meeting in Burma last April with one of the insurgents, Col. Khun Sar of the Shan United Army, about ways to cut back the opium trade. Bourne estimated that Khun sar controls about one-third of the opium-market there.

Wolff said less heroin is coming into this country from Mexico because of greater cooperation between the American and Mexican governments. Many people fear the slack will be taken up by added supplies from Northern Burma and Thailand, he said. Although no breakdown was available for Burma, Southeast Asia supplies an estimated 7 per cent of all heroin smuggled into the United States.

He emphasized that any plan to buy opium would have to be between the insurgents and a local government or international consortium. But Bourne said the plan had "little validity."

"It is unthinkable," he said, "that any representative of this administration would negotiate with representatives of insurgent groups opposed to the legitimate government of Burma much less use the American taxpayers' dollars for a program that would in effect provide a subsidy for narcotic traffickers and arms for an insurrection."

Bourne defended the administration's present strategy of helping the Burmese government destroy opium fields and said it would result in the "near elimination of illicit Burmese opium. He siad the quality of street heroin is the lowest in seven years, which means the supply has been reduced.

The United States has supplied the Burmese government with 18 helicopters to use in destroying opium fields. Bourne defended sending them four more, and said the program to get Burmese farmers to convert to other kinds of crops is working.

But Wolff and other members of the committee said that, because the Burmese government controls so little of the countryside, efforts to deal only through government officials, and not with the insurgents as well, makes the whole program futile. He said in an interview that so far, the Carter administration has assigned a higher priority to having good relations with the Burmese government (by not dealing with the insurgents) than protecting Americans by reducing the heroin supply here.

Wolff said he was troubled by the sending of helicopters to Burma, which could be used against the insurgents. He said he didn't want to repeat "major errors" of the Vietnam era, where supplies sent for one purpose were used for another.