William Greenwood Langston, 52, a former industrial arts teacher in the Washington area who was president of his own market research and public relations firm, died Saturday as a result of injuries he received in an automobile accident in Montgomery County.

A spokesman for the Montgomery County Police said Mr. Langston was traveling at a high rate of speed over wet pavement on Route 108 when he failed to negotiate a curve about a mile west of Olney Mill Road. The spokesman said Mr. Langston's vehicle struck a utility pole. Mr. Langston way pronounced dead at the scene.

Mr. Langston founded his own firm, Langston Associates, specialing in market research and public relations for the agricultural industry, in the mid-1960s. He remained its president until his death.

In addition to running his business, Mr. Langston was an industrial arts teacher at George Mason High School in Falls Church from 1968 to 1974 and at Andrew Jackson Junior High School in Prince George's County from 1974 to 1978. He then was a substitute teacher in the Howard County School system through the end of this year.

Mr. Langston was born in South Carolina and reared in Halifax County, Va. He was a 1950 graduate of the Virginia Polytechnic Institute and earned a master's degree in agricultural economics at VPI in 1954. From 1950 to 1953, he was an Air Force pilot.

From 1957 to 1963, he was a marketing specialist with the agricultural extension service at the University of Maryland, served on the Maryland Egg Promotion Committee and was a coordinator between the state economic development committee and the poultry industry.

Mr. Langston had lived in the Washington area since 1954 and was a resident of Rockville at the time of his death.

Survivors include his wife, Joann Howkes Langston of Rockville; a son, Willian Jr., of Knowville, Tenn.; four daughters, Lee, of Palm Springs, Calif., Susan, of Dallas, Nancy, of Hanover, N.H., and Joy, of Rockville.

The family suggests that expressions of sympathy be in the form of contributions to the Disabled American Veterans.