Melvin R. Jones, 57, a construction engineer for the Bechtel Corp. since 1969, died yesterday at the Southern Maryland Hospital Center in Clinton. He had suffered from cancer.

He was chief of the firm's soil and concrete testing laboratory in Seat Pleasant, where work is being done in connection with Metro construction.

Mr. Jones was born in Lancaster, Pa. He attended Pennsylvania State University. During World War II, he served with the U.S. Army in England and France.

After the war, he returned to Lancaster, where he worked for a railroad, owned and operated a service station and then became a civilian employe of the Army Engineer Corps. He worked for the Army Engineers in Marquette, Mich., for several years before transferring to Washington.

From 1967 to 1969, Mr. Jones owned and operated the Southeast Concrete Co. in Prince Gerge's County.

A 32nd degree Mason, he was a member of Seat Pleasant Lodge No. 218. He belonged to the Forestville Elks Club.

He is survived by his wife, Elizabeth, and a son, Jere, both of the home in Upper Marlboro; another son, David, of Camp Springs; a daughter, Deborah Jones, of Alexandria; a brother, John, and two other sisters, Reba O'Day and Ethel Nolt, all of Lancaster; another sister, Myrtle Wolfe, of Silver Hill, and two grandchildren.

The family suggests that expressions of sympathy may be in the form of contributions to the American Cancer Society.