Six students at top city high schools are suing Defense Secretary Rumsfeld and the Department of Defense for violating their right to privacy.

The New York Civil Liberties Union filed a lawsuit in federal court yesterday on behalf of the students, charging that the department is violating federal law by maintaining an unauthorized database of personal information on millions of high school students across the country for the purpose of military recruiting.

The president of the NYCLU, Donna Lieberman, yesterday called the database a “gross invasion” of privacy.

Even students who fill out forms asking to be excluded from military recruitment efforts are put onto a special “suppression” list, she said.

“Students thought that they could opt out. As it turns out, the information monster is really gathering information willy-nilly,” Ms. Lieberman said.

A spokesman for the Defense Department, Lieutenant Colonel Barry Venable, said he could not comment on pending litigation. Facing increased difficulty in enlisting new recruits, military officials have said that reaching out to young Americans is crucial in order to maintain an all-volunteer force.

One of the plaintiffs, Eleni Healey, a junior at the elite Trinity School on the Upper West Side, said more military recruiting material has landed in her mailbox than college brochures.

“I never exactly thought of myself as the prime military recruiting target,” Ms. Healey said. She lives in Manhattan and plays varsity tennis and runs track.

She said she has been unable to remove herself from the military recruitment list despite submitting the opt-out form she received at school.

“If the Department of Defense wants us to fight for our government and for our country, let us first have the confidence that we shall be fighting for our rights and not against them,” Ms. Healey said.

The information gathered includes names, addresses, telephone numbers, e-mail addresses, Social Security numbers, ethnicity, grade point averages, fields of study, and college intentions.

Privacy advocates attacked the Pentagon’s Joint Advertising Market Research and Studies office when it posted a public notice about the database last year.

In 1982, Congress passed a law authorizing the Defense Department to gather information about American high school students. That law limited the department to gathering information on students ages 17 and older and mandated that files must be erased after three years.

Last year, the department placed a notice in the federal register on May 23 announcing changes to the program to allow for more extensive data collection. Those changes had already been in place for a year before the notice was posted, a spokesman for the department told reporters last year.

Ms. Lieberman said yesterday that the department used private companies to compile the extensive data on students.

Hope Reichbach, a senior at Hunter College High School, is another plaintiff in the lawsuit. She contacted the NYCLU after military recruiters continued to send her information despite being asked not to. She is the daughter of a Brooklyn judge, Gustin Reichbach, a 1960s radical known for displaying a neon “scales of justice” in his courtroom and dispensing condoms to prostitutes in night court.

The other students named in the lawsuit attend the Brearley School, Bard High School, Townsend Harris, and the High School for Environmental Studies.