Under Chilean law, if medical tests were to uncover any signs of dementia or insanity, General Pinochet would be excused responsibility for any crimes on grounds of diminished responsibility.
News of Judge Juan Guzman's decision came through on local media on Monday, the night before the interrogation was due to take place.
It was also reported that Judge Guzman had decided to give the 85-year-old general another chance to show up for medical tests which he failed to attend on Sunday.
A court earlier upheld an order for General Pinochet to attend an interrogation over alleged human rights abuses and ordered him to appear for questioning on Tuesday.
But the general's lawyers insisted that he would not show up and were appealing against the decision in the Supreme Court.
Medical tests - needed to determine whether General Pinochet is fit to stand trial on charges of human rights abuses - have been rescheduled for Thursday and Friday.
No guarantee
No immediate reason has been given for Judge Guzman's decision, but the BBC correspondent in Santiago says it will calm the atmosphere in the case.
Until now there had been talk of the judge ordering the general's arrest for contempt of court.
But to many in Chile, the decision to reschedule the tests and the questioning is no guarantee that either procedure will actually go ahead.
Under Chilean law, if medical tests were to uncover any signs of dementia or insanity, General Pinochet would be excused responsibility for any crimes on grounds of diminished responsibility.
His lawyers have long maintained that General Pinochet - who suffers from diabetes, a series of cardiovascular diseases and alleged memory loss - is not fit to stand trial on human rights abuse charges.
Grim findings
On Sunday, Chilean President Ricardo Lagos presented the results of an inquiry into the whereabouts of more than 1,000 people killed during 17 years of military rule and whose bodies have yet to be found.
The bodies of 151 people, he said, had been thrown into the sea, lakes or rivers and would never be recovered.
Another 20 bodies are believed to lie in a mass grave somewhere in Santiago.
President Lagos called the information raw and painful. He admitted that it was not enough, and the fate of hundreds of Chile's disappeared remains unknown.
He was also careful to make no mention of General Pinochet - in keeping with his belief that the former military leader's fate is a matter for the courts.
The commission's findings came as a disappointment to many Chileans who lost relatives and friends during the Pinochet era.
Human rights activists have criticised the Chilean armed forces for failing to provide more information on the fate of those missing since military rule.