Attorney General Griffin B. Bell apparently feels confident that he will not be thrown in jail next week for refusing to obey a federal judge's order to turn over confidential FBI informer files. He is planning to leave the country.

He's winging off Monday to Australia, aides say, on a long-planned three-week trip that started out as mostly vacation and has ended up as mostly speech-making.

Bell's attorneys today are expected to file an appeal of the order by U.S. District Court Judge Thomas P. Griesa to hold the attorney general in civil contempt if he hasn't turned over the disputed files in the $40 million Socialist Workers Party suit by tomorrow. But the appeal is not expected to delay the trip.

The jaunt down is the brain child of Philip H. Alston Jr., an old Bell acquaintance from Atlanta, who is now U.S. ambassador to Austrlia. The visit will include stopovers - and speeches - in Canberra, Sydney, Melbourne and Tasmania, and then a side trip to New Zealand, according to the State Department itenerary.

Bell was briefed last Friday by Richard Holbrooke, assistant secretary of state for East Asian and Pacific affairs, on likely topics of interest to the Australians. Among them are the fate of refugees form South-east Asian and interational antitrust matters, such as Australia's alleged role in an international uranium cartel.

The attorney general's aides have been a litte defensive about justifying the three-week trip at government expense, though it is winter in the Southern Hemisphere. But they have been more easygoing about it lately because of Bell's packed schedule. "I don't have any trouble justifying it anymore," one aide said yesterday.

Last year Bell traveled abroad only to London and Ottawa for legal conferences. The trip to Australia seems to have whetted his appetite, however.

In August, a spokesman said, the attorney general plans a journey to India for a seminar on the media, law and government in Delhi.

And late in the fall Bell is to go to Israel at the invitation of the chief justice of the Israeli court system to deliver a university lecture.