National Symphony executive director Henry Fogel yesterday was appointed to one of symphonic music's most important management jobs, executive director of the Chicago Symphony Orchestra.

The Chicago Symphony, in its 15th season under music director Sir Georg Solti, would be on just about any expert's list of the world's half-dozen finest orchestras.

Fogel, 42, succeeds John Edwards, who died last August. Fogel will assume his new duties Aug. 1, although a Chicago Symphony spokeswoman said, "He will spend time in Chicago on a regular basis before then." Fogel also will carry the title executive vice president of Chicago's Orchestra Association. His salary reportedly will be about $140,000.

During his five years here, Fogel was given wide credit not only for improved management efficiency at the NSO, but also for initiating fresh programming and selecting new soloists and conductors.

NSO music director Mstislav Rostropovich, reached in Brussels last night after a concert, said, "During Henry's time here, we worked well and in complete accord for the benefit of the National Symphony Orchestra. Now I hope that the Chicago Symphony will have the same benefits. I wish him every success and hope that his wonderful family settles quickly and happily into their new city."

The president of the National Symphony Association, Virginia C. Mars, said in a statement: "We are indeed sorry that Henry Fogel is leaving us. But at the same time we are pleased both for Henry and the Chicago Symphony. They are getting an extremely talented professional who has done a great deal for the National Symphony Orchestra. He will be missed."

Mars said a search committee for a new executive director should be "in place by the end of the week."

In Chicago, Solti said: "Over the past 15 years I worked with John S. Edwards in the greatest warmth and friendship, and I look forward to developing just such a close and friendly relationship with Henry Fogel . . . We look forward to our 100th anniversary in five years, and the directions we take now will chart the orchestra's future course. I am confident that it will be an exciting and productive time."

It is believed that Solti, 72, will stay on at the symphony at least through the orchestra's centennial.

Fogel was chosen for the Chicago symphony by a search committee consisting of trustees and two members of the orchestra. Last Friday, the panel's choices had been pared to three. The symphony declined to release the names of the other two contenders.

Fogel came into symphony management from the world of classical music radio. From 1963 to 1978 he was vice president and program director of station WONO in Syracuse, where he conceived and produced the first radio fund-raising marathon for an orchestra. During the five years before coming to Washington, Fogel served as orchestra manager of the New York Philharmonic.

He was unavailable for comment yesterday, but in a statement issued through the Chicago Symphony, Fogel said: "Ever since I became interested in music, it has been clear to me that the Chicago Symphony Orchestra is one of the very finest in the world. To have received the honor of working with this institution and its truly great music director . . . is, frankly, something it will take me a while to get used to.

"There are enormous challenges ahead of us, particularly in the area of building the solid fiscal foundation that such a great artistic institution merits."