Labor Secretary William E. Brock told Congress yesterday that the administration opposes an increase in the $3.35-an-hour minimum wage and said the poor would benefit more from improvements in education and job training.

"We believe that the increase is bad policy, especially in the context of today's economy," Brock told the Senate Labor and Human Resources Committee. "It will hurt younger workers, it will not reduce poverty, and we oppose it."

The hearing followed the release of a report by the Center on Budget and Policy Priorities that concluded a full-time worker earning the minimum wage of $3.35 an hour takes home $6,968 a year. That is about 20 percent below the poverty line for a family of three.

While the minimum wage has not been raised since 1981, consumer prices have increased 30 percent. If adjustments for inflation are considered, the value of the minimum wage is at its lowest level in more than three decades, according to the center, which is an independent nonprofit research group that studies issues affecting the poor.

In its report, the center called for a $1-an-hour increase in the minimum wage. According to the center's calculations, $4.35 an hour would put those workers near the poverty line. The document also suggests linking future increases in the minimum wage to changes in inflation.

"To continue to keep the minimum wage at $3.35 an hour for an indefinite period would suggest that we are willing to accept its gradual erosion to the point where it may cease to have much meaning," said Robert Greenstein, the center's director.

In the 1960s and 1970s, the minimum wage generally enabled one full-time worker and two dependents to have enough income to be above the poverty level, the center said. In 1986, the minimum wage provided an income equivalent to 77 percent of poverty level.

According to the survey, 6.7 million Americans earned the minimum wage or less in 1986. Of those workers, 48 percent were older than 25 and nearly two-thirds were women.