The Washington Post Co. yesterday reported its profits grew more than 25 percent last year to $85.9 million ($6.11 a share) from $68.4 million ($4.82) in 1983.

The media company's annual revenue climbed 12 percent, to $984.3 million from $877.7 million. For the final three months of the year, revenue was up 11.5 percent to $283.6 milion, from $254.3 million in the same period a year earlier, and fourth-quarter earnings gained almost 21 percent, to $34.6 million ($2.47) from $28.6 million ($2.02).

"Strong results from all three divisions contributed to our progress in 1984," said a statement issued by Chairman Katharine Graham and President Richard D. Simmons. "We believe the company is well positioned to enhance the quality of its publications and programming, while achieving significant earnings growth in the future."

The Post company said operating profits of its newspaper division climbed almost 20 percent to $94.6 million from $78.9 million, while total revenue grew 13.4 percent to $516.6 million from $455.7 million. Total advertising lineage at The Washington Post grew 8 percent -- to 5.2 million inches from 4.8 million inches -- and ad revenue of the paper was up 14 percent.

"Newsweek's continued improvement was a cause of special encouragement," the two top executives said. The magazine's operating income jumped 42.8 percent to $21.9 million from $15.3 million, and revenue was up 9.7 percent to $331.6 million from $302.2 million. Domestic editions of Newsweek carried 3,009 pages of advertising for the year, compared with 2,937 pages in the previous year.

Operating income of the Post's television stations showed a 28.8 percent increase to $50.8 million from $39.4 million, while broadcasting division revenue was up 13.6 percent to $136 million from $119.8 million.

The company said its stake in the operations of affiliated businesses produced a $5.7 million loss for the year, compared with earnings of under half a million the previous year. The company's share of the earnings of two paper mills grew by about $3 million, while there was a $7.5 million increase in the losses of the Sportschannel cable television operations. Those operations were acquired between July 1983 and January 1984. Earlier this week, the Post announced that it had sold a part of its interest in four cable television sports channels for a gain of 40 cents a share.

For the fourth quarter, revenue was up 11.5 percent in the newspaper division, 11.3 percent at Newsweek and 13.7 percent for the television stations.