Christianity Today, the leading evangelical intellectural journal since its establishment 20 years ago under the leadership of evangelist Billy Graham, will move from Washington to suburban Chicago, in the heartland of conservative Protestantism.

A majority of the biweekly magazine's board of directors approved the proposal Tuesday despite objections by most of the staff. The directors cited as major advantages in relocation anticipated financial gains and accessibility to the nations's largest theological center.

However, several persons familiar with the magazine believe an equally important factor is the feeling of some board members that Washington is too "polluted" an atmosphere for a religious publication.

Harold Myra, publisher for 18 months, acknowledged that "a lot of speeches were made about the 'poisonous atmosphere' of Washington back in the Watergate days." But he insisted that position "is not a broad consensus of the broad."

All but two members of the editorial staff opposed the move. Those two abstained. A principal argument against moving was that the magazine's presence in Washington is important at a time of increasing involvement of evangelicals in social and political affairs.

Christianity Today, which had a circulation of 127,000 rents the 10th floor of the Washington Building, at 1435 G St. NW.

Myra said the move was prompted by high costs of office rental or building purchase in the Washington area. The directors ruled out relocating in Northern Virginia.

The magazine will purchase a 12,000-square-foot building in Carrol Stream, III., and complete the move by summer, he said. "We need equity," Myra said.

About two years ago, Christianity Today had a deficit of nearly $1 million, according to Graham. The financial crisis was exacerbated by a drastic reduction in contributions from the Glenn Meade Trust Controlled by the late Howard Pew of Philadelphia, former head of the Sun Oil Co. His money provided a major subsidy to the magazine for years.

Founded as a magazine for preacxers, Christianity Today originally was distributed free. The subscription rate is now $15 a year. Myra said the goal is to be self-supporting by 1980.

Myra conceded that costs of living and business operations in Chicago are not greatly different from Washington. "But Chicago is better," he said, "about 10 per cent better. It will allow us a more efficient operation."

By going to Carrol Stream, the magazine will be within a few miles of Wheaton, the Chicago suburb known as the "mecca" of independent evangelicalism in the United States. Such major organizations as the National Association of Evangelicals and Youth for Christ, and other small, evangelical denominations and mission societies have headquarters here.

The Graham denter and archives, a major complex, is being developed at Wheaton College, Graham's alma mater.

Graham, a Southern Baptist, supported the magazine's inception with his father-in-law, the late Dr. Nelson Bell, a Presbyterian, as a voice of and to evagelicals in mainline denominations. Graham also backed the Washington location.

What borders some persons associated with the evangelical movement is that the new location many mean the magazine will gradually become oriented toward independent evangelical denominations and organizations that are less influential in the nation's social and political affairs. This is particularly irksome to them at a time when evangelicals are experiencing a resurgence of power in the nation.

Graham did not attend the board meeting because of doctor's orders to slow down. He is suffering from phlebitis. He said he "would not know how to vote" under the circumstances. "But I think in the long view, they must take into account the financial situation," Graham said.

Graham heads a committee that is looking for a new editor-in-chief for Christianity Today, a decision many hold to be more significant than the location of the publication.

Harold Lindsell, the current editor, announced his retirement this year. He has abstained in discussions of publishing sites.

Graham said "about three or four" persons are under serious consideration. The preference is a theologian with an earned doctorate.