A broad range of health, minority, women's and environmental groups, protesting what they say is an attempt to kick them out of the federal government's annual charity drive, have asked President Reagan to reject a United Way proposal to limit eligibility in the Combined Federal Campaign.

Most of the groups were admitted to the CFC under the terms of an executive order issued last year by the president. They said they have heard the White House is considering issuing a new order that would result in about three dozen "nontraditional" charity organizations being kicked out of the campaign, at an estimated loss to them of more than $4.5 million.

"Federal employes like having a broader range of charities to support," the groups said in a letter to Reagan signed by 18 organizations, among them the Native American Rights Fund, the Committee for Responsive Philanthropy, the Center for Science in the Public Interest, and legal defense funds for Federally Employed Women and the Sierra Club, They urged him to reject the United Way proposal as directly contradicting Reagan's efforts to increase private giving.

Last September, United Way of America asked the White House to restrict participation in the CFC to "charitable agencies providing direct, human-care services in the fields of health and welfare, including health research." United Way argued that inclusion of less traditional service groups had hurt charity contributions.

The example cited in the letter to Reagan was the National Right to Work Legal Defense Foundation, whose admittance to the CFC last year, United Way said, had sparked a boycott of the campaign by some unions.

CFC raised $87 million in employe contributions in 1981, $12 million of it in the Washington area. But a controversy in recent years over the number and types of organizations that should be allowed to participate has kept the campaign in legal and political upheaval.

Some groups, usually those long established in the drive, have argued that opening the campaign to many, new organizations confuses givers and spreads contributions too thin. But groups who have gone to court to gain admittance say expanding the CFC has increased overall donations by providing a wider choice of charities.

" . . . When employes have more choice of charities to support, they give more," the charity groups said in their letter, to be sent to Reagan today. They said that, according to the Office of Personnel Management, charitable giving in federal offices is up more than 7 percent this year, the first time since 1977 that the increase in giving outpaced inflation.