More than 100 bus drivers for Gold Line-Gray Line, one of Washington's largest tour-bus operators, voted overwhelmingly yesterday to strike if the company does not drop demands for pay cuts.

The company, which carries more than 1 million sightseers and charter customers a year and runs commuter service between Washington and Fairfax City, Charles County and St. Mary's County, has sought reductions in pay, sick leave and other benefits, according to Local 1098 of the Amalgamated Transit Union, which represents the drivers.

Drivers voted 106 to 12 to reject a contract offer and to strike, possibly as early as today, said Al Banks, a union spokesman.

The company is scheduled to meet with the union today in an effort to avert the strike, said Leonard Hanson, director of operations for Gold Line Inc., which also does business as Gray Line.

"I have no comment, other than that they have rejected our offer," said Hanson.

A one-year contract with the drivers expired Jan. 15, but had been extended to yesterday.

Drivers earn from $7.37 to $8.37 per hour, but many could lose up to 50 percent of their income under new pay scales and work rules proposed by the company, Banks said.

In addition to a proposed pay cut of some 5 percent, the company is proposing to eliminate a rule that guarantees drivers a minimum of four hours' pay when they are called to work, Banks said. Because drivers are often called to work on short runs, he said, many would lose substantial income.

A proposed sick leave rule would also require any driver with five or more absences in nine months to take a five-day leave without pay and obtain a medical exam at his own expense before returning to work, Banks said.

The company said it must impose cuts because it lost money in 1984, "but we think this is a case of inordinate corporate greed," he said.

Banks also said the drivers, many of whom are black, are seeking changes in the firm's disclipinary and promotion policies which they say are racially discriminatory. Hanson would not comment on those allegations.