A group of minority businessmen who feel their livelihoods are threatened by the Reagan administration, and a group of black Republican appointees, last night demonstrated the ritual of social cordiality.

In a small room of the Rayburn House Office Building, the Business Policy Review Council and other minority entrepreneurs honored three Reagan appointees, hoisted their drinks to the appointees' good health and danced around their differences. "They don't understand," said Chester Lewis, who operates a construction and service industry business in Leavensworth, Kan. "I find the administration doesn't understand the 8-A program, for example [in which contracts are awarded on a noncompetetive basis for minority firms]. They don't understand helping minority business stay on its feet." Besides a 25 percent overall cut in Small Business Administration loans, the administration has also proposed revamping the criteria for 8-A contractors to eliminate those who have participated for three to five years.

HUD Secretary Samuel Pierce, who like the other appointees was hearing the harshest criticism over the wine and cheese, said "I believe our economy is very ill and until we improve and correct the economy, it will be bad for all people. I have found out that the rural poor are bearing more of the cuts than the urban population."

The principle honorees at the reception were Melvin Bradley, the senior policy adviser in the Office of Policy Development, Thelma Duggin, a deputy special assistant in the Office of Public Liaison and Thaddeus Garrett, the domestic policy adviser for the vice president. But other appointees showed up including Pierce, Dan Smith of the Office of Policy Development, Toni Ford, who has been nominated to be AID Near East director, and Robert Wright who is rumored to be the choice for assistant administrator at SBA. When told of the harsh criticism of Reagan's policies, Wright said, "I don't think it's true."

When Bradley, Duggin and Garrett all came to the microphone, they expressed the same wish for a cooperative, supportive relationship. The 150 people facing them all listened, keeping the anger they expressed earlier to each other private, and putting on a public face of conciliation. Fred Black, General Electric's manager for special interest groups and the current council president, only spoke of developing a working relationship. He said the reception was to "provide access for our membership. There is no overall strategy and no monolithic viewpoint."