A Montgomery County grand jury yesterday indicted six men and a woman on charges of sexually abusing five young children -- indictments that the county prosecutor called an unprecedented number for one day.

The seven cases reflect a national trend in which more and more cases of sexual abuse of children are being reported, a trend that social workers and law enforcement officials attribute to increased public awareness of the problem.

"This is a record. We've never had a day since the county was formed where we've had seven cases of sexual abuse of children indicted in one day," said Montgomery County State's Attorney Andrew L. Sonner.

All the cases in Montgomery involved the children's caretakers, shattering the myth that abuse usually involves a stranger bribing a child with candy.

"You've got it all right here: father, boyfriend, grandfather, babysitter, mother, stepfather," said Lt. Robert L. Hill, director of the Montgomery County police's youth division.

Cases of sexual abuse of children, Hill said, "are becoming a national concern now, as drugs were in the '60s."

The cases also illustrate that sexual abuse of children occurs among all professions and income levels, according to Michael Fitzgerald, a social worker with the county's Protective Services department.

In Montgomery County, 469 cases of sexual abuse were reported in the 1984 fiscal year that ended June 30, according to figures released by the county Sexual Assault Service. This represents a 13-fold increase over the 36 cases reported by the county Department of Social Services in 1979.

Between 1976 and 1982, the number of cases of child abuse reported across the nation increased 123 percent, according to the National Center on Child Abuse and Neglect. The center estimates that 6 percent of the total reported cases involved sexual abuse.

"I do think Montgomery County is a microcosm of the United States and, secondly, we've got one of the most sophisticated and sensitive law enforcement apparatuses in the country," Sonner said yesterday.

"If the number of cases is influenced by the williness of the public to report, Montgomery County is going to be in the forefront nationally."

To deal with the growing caseload, the police department's Child Abuse Sexual Offense Investigative Team, formed in July 1983, doubled its staff to 12 officers earlier this week, Hill said. Police expect that the number of child abuse cases will continue to rise, since a state law that went into effect Oct. 1 requires police or protective services officials to respond to reported cases within 24 hours and complete their investigation within 10 days.

Sonner's office has applied for a $40,000 federal grant to coordinate efforts among about a dozen county agencies and private groups to deal with sexual abuse of children.

Indicted yesterday on charges of child abuse and various sex offenses were: John Alfred Clark, Jr., 38, of 1120 Veirs Mill Rd., Rockville, a professional with a high-technology firm; Sandra Wallace Contee (age and profession unavailable), 14661 Woonsockett Dr., Wheaton; Quentin David Proctor, 32, of 1430 Belmont St., NW, Washington, a dockloader; James DeBevoise Sheldon, 45, an intake worker with the county Department of Juvenile Services and Irving Herson Mayer, 69, a self-employed consultant, both of 19827 Bazzellton Place, Gaithersburg; Emile Farah Haddad, 36, of 12904 Matey Rd., Wheaton, a supermarket produce clerk and James Alpheus Jones, Sr., 59, of 18691 Cross Country Lane, Gaithersburg, vice-president of a Washington electronics firm.