Erling Diesen (born 6 July 1932) is a Norwegian engineer and civil servant. He was born in Geithus, finished his secondary education in Hønefoss in 1951 and graduated as a civil engineer from the Norwegian Institute of Technology in 1956. He worked at the Institute of Technology as engineer and research assistant until 1960, and was a secretary in the from 1960 to 1961. He was hired in the Norwegian Water Resources and Electricity Agency in 1961, and was a chief engineer in the power plant department until 1977 and in the electricity department from 1977 to 1978. He was then a subdirector in the Norwegian Ministry of Petroleum and Energy from 1978 to 1980 and then as subdirector in the Water Resources and Electricity Agency from 1980 to 1983. He was the chief executive officer of from 19