William E. Andrus Jr., 57, a vice president and technical director of the National Electrical Manufacturers Association and a former official of the National Bureau of Standards, died of cancer Sunday at the Shady Grove Adventist Hospital in Rockville.

Mr. Andrus came to Washington in 1970 and spent a year as a statistical and computer consultant to the National Bureau of Standards. A year later, he became a full-time member of the bureau's staff. He helped conduct its first program of computer resource utilization measurement. He also worked on projects involving engineering and product standards.

In 1973, he was acting deputy assistant secretary of commerce for product standards. In 1975, he was named chief of the bureau's Office of International Standards.

Mr. Andrus retired from the government in 1979 and joined the National Electrical Manufacturers Association, a trade organization representing manufacturers of electrical products. Mr. Andrus worked there until his death.

He was a fellow of the Standards Engineering Society and a member of the Institute of Electrical and Electronics Engineers. He had served on the board of the American National Standards Institute and had been a U.S. representative on the Pan-American Standards Council and the International Electrotechnical Commission.

Mr. Andrus was a native of Binghamton, N.Y., and a graduate of Syracuse University. He was a Navy flier during World War II and served in China and the Philippines. His decorations included the Air Medal.

He was an engineer, statistician and manager with the IBM Corporation for 21 years before moving to this area in 1970 to become a consultant and then a government official. He lived in Gaithersburg and had been active in the Boy Scouts there.

Survivors include his wife, Nancy of Gaithersburg; three sons, Bill of Chelmsford, Mass., Jim of Auburn, N.H., and Teddy of Gaithersburg; two daughters, Carol Russell of Gaithersburg, and Susan Neal, of Columbia; his father, William E. Sr. of Johnson City, N.Y., and four grandchildren.