He’s the Grinch who stole Gucci — at least for one day last summer.

A disgruntled former computer tech at Gucci’s U.S. headquarters in Manhattan was slammed with a 50-count indictment today for allegedly hacking into his old system — where he wreaked havoc, prosecutors said.

The alleged high-tech mischief of Sam Chihlung Yin, 34, of Jersey City, crashed the computers of the luxury goods retailer for nearly 24 hours one day last June, leaving Gucci unable to access documents and email, Manhattan DA Cyrus Vance said in announcing Yin’s indictment.

Store managers across the country, along with the online sales staff, were hamstrung all day, resulting in some $200,000 in sales losses, Vance said.

Other documents and emails were zapped into oblivion permanently, prosecutors said.

Yin had been terminated from Gucci for abusing his employee discount to buy Gucci goods in bulk, then ship them to Asia for resale, assistant district attorney Ehren Reynolds told the judge.

He pleaded not guilty in Manhattan Supreme Court and was released without bail.faces up to 15 years prison if convicted of the top charge against him: first degree computer tampering.