New Jersey's last-known vestige of official discrimination, an 80-year-old statute permitting municipalities to regulate ''roving bands of nomads, commonly called Gypsies,'' is about to be repealed.

The demise of the law was unanimously approved by both houses of the New Jersey Legislature and is on Gov. Christine Todd Whitman's desk awaiting her signature, Pete McDonough, a spokesman for the Governor, said. He said he expected her to sign the bill.

The statute, enacted in 1917, allowed local governments to make laws and ordinances to license the various forms of transportation used by Gypsies, like horse-drawn carts, as well as their businesses, any goods they sold, places where they were entertained and where they could rent property.

''The law was unquestionably discriminatory and an insult to many New Jersey residents,'' said the author of the repeal legislation, Assemblywoman Nilsa I. Cruz-Perez, a Democrat from Camden.

''I was shocked when I learned earlier this year that the law was still on the books,'' said Mrs. Cruz-Perez, a native of Puerto Rico who was the first Hispanic woman elected to the New Jersey Legislature. ''This is a multiracial society, and even though no one would now ever think of enforcing such a law, it's embarrassing.''

''Can you imagine, arriving in a town and having to tell village officials why you're there, what you plan to do, where you plan to stay and when you're leaving,'' she added.

Abraham Foxman, national director of the Anti-Defamation League and a member of the President's Holocaust Memorial Council, welcomed the New Jersey Legislature's action. ''I think the very fact that such a stain has been expunged is cause for celebration,'' he said.

''There is no question in my mind that there are other similar discriminatory laws in states across the country,'' Mr. Foxman said, ''but hopefully, this will spur people to do some research, dig them out and get rid of them.''

The Gypsies trace their ancestry back more than 1,000 years to a caste in northern India that speaks the Romany language, said Martin Hochbaum, former regional director and president of the New Jersey region of the American Jewish Congress. He said the medieval misconception that the Gypsies originated in Egypt was the derivation of the word Gypsy.

In an opinion article in the New Jersey section of The New York Times early last year, Mr. Hochbaum likened the Gypsies' persecution to that of the Jews, noting that Nazi Germany killed tens of thousands of Gypsies.

A long history of persecution caused many of the Gypsies to seek a new life in the United States, he said in the article. World War I marked the end of the first migration of the Gypsy people from Europe to America.

''It coincided with a period in which xenophobia was common through the nation, a hostility to strangers that took the form of employment discrimination and attacks on the use of teaching languages other than English,'' he wrote.

Mrs. Cruz-Perez said the fact that the law was still on the books was brought to her attention by members of a Jewish community group in her Assembly district. She said support to repeal the measure came quickly from the American Jewish Congress as well as other Jewish and Roman Catholic groups.

''Surprisingly, I have not heard from any Gyspies, not even a letter from someone who remembered their grandmother or grandfather talking about the old law,'' Mrs. Cruz-Perez said. ''Perhaps that old discrimination causes them to continue to deny their heritage.''

She said that she knew of no official figures indicating how many Gypsies lived in New Jersey.

On a visit to Atlantic City this past summer, Mrs. Cruz-Perez said that she sought to talk to people who advertised themselves as Gypsy fortunetellers. ''But when I asked them if they were Gypsies, they said, 'No,' but they thanked me anyway for getting rid of the old law,'' she said. ''I soon realized it didn't matter if they were Gypsies, Hispanic, Italian, Irish or any other people. A discriminatory concept like this should not exist in this country.''

Mrs. Cruz-Perez said that her staff had carefully searched New Jersey's laws and felt certain this was the last remaining discriminatory law. But she said there still might be others ''hidden in the books somewhere, not only in New Jersey, but in states across the country.''

''Let's face it,'' she said, ''there are thousands and thousands of old forgotten laws. But maybe the repeal of this law may encourage others to take a closer look at their own laws.''

''History has taught us some lessons about what can happen when one group discriminates against another,'' Mrs. Cruz-Perez continued. ''It's a slippery slope that opens the door to discrimination against more and more groups, which is a prescription for tragedy.''