The charges were announced five days after a sex scandal broke at the military's Aberdeen Proving Ground in Maryland.
The three soldiers at Fort Leonard Wood face charges ranging from consensual intercourse to indecent assault, or touching. Army regulations ban sexual relationships between commanders and subordinates. The recruits were 21 years old on average and were undergoing basic training.
The Army did not say when the charges were filed. One court-martial was to begin yesterday; the others will be conducted within the month, it said.
A Pentagon spokesperson said there was no connection between the Fort Leonard and Aberdeen cases. The Fort Leonard cases came to light before the Army set up a hot line for reports of sexual misconduct, said Lt. Col. William Harkey.
The Army did not identify the Missouri soldiers except to say that all are non-commissioned officers and that one or two are drill sergeants. Other allegations of misconduct at Fort Wood were also under investigation.
At the Army Ordnance Center at the Aberdeen Proving Ground, the Army last week charged four drill instructors and a captain with raping, sexually harassing or otherwise having improper relationships with at least a dozen young women recruits in their first weeks of training at Aberdeen.
The men were suspended along with 15 other instructors.
The Army said trainees at Fort Wood are told their first day on the base how to report harassment or uncomfortable situations involving other soldiers.
Yesterday, the Army allowed reporters to speak with a group of Fort Leonard trainees who have been in the military for about six weeks. None of the women said they felt sexual pressure or harassment.
"My drill sergeants are very, very helpful to us," said Pvt. Sheila Stanton, 20, of Frostproof, Fla. "They train us hard, they treat us as equals to the males. They've never done anything to make us feel uncomfortable."
An angry Pvt. Eric Beckham said the accusations had tarnished others.
"Our drill sergeant has a black mark on him because of what some people did or they did not do," said Beckham, 21, of Abilene, Texas. "It's not right."
About 25,000 soldiers pass through the Missouri base each year, making it the second-largest of four posts where the Army conducts its basic training. Only Fort Jackson, S.C., is larger.
The post's main mission has been to train officers, non-commissioned officers and enlisted soldiers in engineering skills. The Army is adding a military police school and a chemical warfare training school, which will add 5,500 people to the base by 1999.
Women make up 25 percent to 30 percent of each class of trainees.
"We have found that's an ideal mix for males and females to complete their training under ideal conditions," said Brad Rose, a base spokesman.
When the Aberdeen scandal broke last week, the Army asked that anyone who had been a victim of sexual misconduct call a special toll-free number at the base near Baltimore. More than 2,000 calls had poured in by Monday afternoon.
Gen. John Shalikashvili, chairman of the Joint Chiefs of Staff, said the Army had to assume such improper conduct was taking place elsewhere. He said officials are looking all across the Army, particularly its training centers, to root out sexual wrongdoing.
A little more than 10 percent of the calls to the hot line were deemed serious enough to refer to the Army's Criminal Investigative Division.
Army investigators at Aberdeen have said they plan to interview as many as 1,000 women who were trained at the post since the beginning of 1995, a process that could take months.