A visit here by U.S. Army Chief of Staff Gen. John A. Wickham Jr. was canceled last week, indicating U.S. uneasiness about Gen. Augusto Pinochet's recent crackdown on internal opposition, according to officials here and in Washington.

Wickham had been scheduled to arrive in Chile last weekend to watch Chilean Army maneuvers at the invitation of Army Deputy Commander Julio Canessa, Pinochet's top military deputy. The trip was called off following the government's declaration of a state of siege Nov. 6.

According to a knowledgeable Chilean source, officials interpreted the cancellation as an expression of U.S. unease over the new repression, which has included censorship, strict limits on freedom of assembly and military raids on two Santiago neighborhoods.

In Washington, Col. Bill Smullen, an Army spokesman, said: "A visit by Wickham was scheduled, but the visit was postponed because it was felt that at this time it would not be productive because of all that is going on down there."

The measure came amid a series of critical public statements by U.S. officials and other western governments reflecting strong diplomatic opposition to the new military policies. The State Department, the Spanish government and the European Community have all questioned the state of siege measure, and the Organization of American States passed a resolution yesterday calling for improvement in human rights here.

Secretary of State George P. Shultz said at a news conference at the OAS meeting in Brasilia Monday that the Reagan administration was "very disappointed" by the Chilean government's actions and added, "I am sure that Gen. Pinochet is aware of that fact."

So far, Chilean authorities have reacted to the diplomatic pressure with shows of public defiance. Foreign Ministry officials refused to accept a protest note from the Spanish government over the expulsion of a Spanish-born priest last week, and the Chilean delegate to the OAS sharply rejected charges in the organization's annual human rights report that conditions in Chile had deteriorated.

Speaking to reporters last week, Foreign Minister Jaime del Valle said that the 11-year-old miltary administration "cannot keep wondering whether or not what we do in Chile is going to be liked by foreign governments. We do what is convenient for the country . . . [and] we are not going to accept appeals."