WASHINGTON (AP) _ Federal regulators have cleared the way for the $550 million sale of the Spanish-language Univision Television Network to a group of U.S. and Latin American investors, despite objections that the deal would limit the diversity of Hispanic programming.

The Federal Communications Commission on Wednesday approved the sale of 15 Univision stations by Kansas City-based Hallmark Cards Inc.

The sale was opposed by numerous Hispanic organizations and Telemundo Group Inc., the competing Spanish-language network.

The buyers are Los Angeles businessman A. Jerrold Perenchio, Emilio Azcarraga of Mexico's Televisa conglomerate and Gustavo Cisneros of Venezuela's Venevision TV network.

Opponents argued that the sale would reduce competition and would give major control of the stations to two foreign owners. It said Hallmark should have sold the stations to Hispanic Americans.

The commission said it was ''unconvinced by the objectors' arguments and found that the buyer was fully qualified to be an FCC licensee.''

Under the approved transfer terms, Perenchio, who is American, will own 75 percent of the stations, and Televisa and Venevision will own 12.5 percent each. U.S. law limits foreign ownership to 25 percent.

The FCC also announced the sale of Hallmark's Univision Television Network to the buyers of the stations. The sale of the network did not require FCC approval but was contingent upon approval of the station sales.

The network will be owned 50 percent by Perenchio and 25 percent each by Televisa and Venevision. Univision reaches about 90 percent of the Hispanic television households in the United States through broadcast and cable affiliates and had revenue of about $200 million in 1991.

Perenchio is co-owner of Embassy Communications that produced the series ''The Jeffersons'' and former owner of the Loews Theaters, a major U.S. theater chain.

Televisa is Mexico's largest television network, and Venevision is the major network in Venezuela.

The sale, which is expected to be completed in December, includes television stations in Los Angeles, Miami, San Francisco, San Antonio, Albuquerque and Phoenix.