Bernardine Dohrn came out of hiding today, still voicing criticism of the society she left a decade ago as a leader of the radical Weather Underground movement.

Dohrn declined to answer questions at a news conference. But in a written statement she said she went underground during a period of "unspeakable crimes" by the U.S. government, adding that "the nature of the system has not changed."

She said she is returning to "an open life with a sense of loss" and still believes "in the necessity of underground work." She voiced concern that Vietnam-type intervention is imminent in Africa and the Middle East.

Dohrn, 38, surrendered at the Cook County Criminal Courts Building and pleaded innocent to aggravated battery and other charges growing out of the so-called "Days of Rage" demonstrations on Chicago streets in October 1969. s

Judge Fred G. Suria Jr. later freed her on $25,000 bond, which required a cash outlay of $2,500, all that her lawyer said she could scrape together.

At Dohrn's side was long-missing William Ayers, 35, another one-time militant member of the Weather Underground and son of Thomas G. Ayers, chairman of the executive committee of Chicago's Commonwealth Edison Co.

No charges have been pending against Ayers for the past six years, since a federal indictment against him was dropped. Asked by a reporter before Dohrn's court hearing why he hadn't appeared in public previously, Ayers said he was aware he faced no charges but "I was living with Bernardine." The couple has lived in New York City under assumed names in recent years.

Charges against Dohrn, in addition to aggravated battery, include mob action and resisting a peace officer. as assistant Cook County state's attorney said that in lay terms, the charges amount to "striking a policeman with a club" and kicking a policeman.

However, Dohrn's attorney, Michael A. Kennedy of New York, told Judge Suria he had studied films of the "Days of Rage" demonstrations and "nothing shows her assaulting or battling anyone." Kennedy said she will contest all charges.

Newly installed Cook County State's Attorney Richard M. Daley, son of the late Chicago Mayor Richard J. Daley, who was a principal target of the radicals' ire in the late 1960s, said before the court hearing that his office had made no plea-bargaining deal with Dohrn's lawyer.

The 1969 demonstrations, in which young people smashed windows and clashed with police on Chicago's North Side and in the Loop, were principally antiwar in nature. They coincided with the federal conspiracy trial of eight persons accused of plotting riots during the 1968 Democratic National Convention in Chicago. A few months after the demonstrations, in early 1970, both Dohrn and Ayers disappeared into the radical-left underground.

During the no-question press conference staged by Dohrn and Ayers, he ruled out any discussion of their decade in hiding.

Dohrn, a native of Whitefish Bay, Wis., who holds a degree from the University of Chicago law school, said in her statement that she went underground to "oppose U.S. intervention in Vietnam; to try to support the black movement for liberation and human rights and to oppose the system built on slavery, genocide and colonialism."

Ayers' statement included an apparent attack on the incoming administration of President-elect Ronald Reagan. He said, "It seems to me the current establishment goal and promise of recapturing U.S. hegemony around the world and prosperity at home can only be attempted through war."