Washington Post Co. President Richard D. Simmons said today the company's publishing and broadcasting businesses enjoyed excellent growth in 1984 and predicted that 1985 would be an even better year.

Simmons, in an upbeat speech to Wall Street securities analysts, said he is encouraged by the underlying strength of the company's businesses, including The Washington Post newspaper, Newsweek magazine, and the company's four television stations. Simmons said all the Post-Newsweek television stations are No. 1 in their markets, an accomplishment he said was "remarkable" because all three networks are represented among them.

The company owns television stations in Detroit, Miami, Hartford and Jacksonville.

Simmons said that while the Post Co. wants to grow, it will not pay the high prices for media properties that it takes to win many bidding wars. He cited The Des Moines Register and Tribune Co's newspaper operations, the magazines of Ziff-Davis Publishing, the New Yorker magazine and U.S. News and World Report magazine as properties that have been sold recently for prices higher than the Post Co. is willing to bid.

"Our primary financial goal remains sustained earnings growth that ranks with the industry leaders," Simmons said.

Simmons said Newsweek operating income jumped 44 percent last year, to $22 million, with gross advertising revenue climbing 13 percent to $247 million. He said Newsweek profit margins, which had been as low as 5 percent in prior years, reached almost 8 percent in 1984, and will be close to 10 percent this year.

Simmons said cutting costs has helped improve Newsweek profit margins, adding that the number of full-time employes dropped 3 percent last year to about 1,150.

Simmons said the Post's newspaper division operating income was up 20 percent last year to $95 million, more than triple the divison's operating income in 1981.