The head of an Arab university in the Israeli-occupied West Bank today condemned as excessively harsh prison sentences of up to two years that have been given to students at the school who took part in a stone-throwing disturbance there last month.

At a news conference, Gabi Baramki, acting president of Bir Zeit University near Ramallah, also accused Israeli military authorities of breaking a pledge not to arrest students who left the campus peacefully at the end of the July 27 disturbance, in which tires were burned and stones were thrown at Israeli soldiers. An Army spokesman said there had been no such pledge.

"The harsh measures taken by the military authorities against our students in the last week seem designed not to punish specific offenses, but to strip our young people of hope and create a generation of despair," Baramki said.

Within the past week, an Israeli military court in Ramallah has sentenced one Bir Zeit student to two years in prison and nine others to prison terms of 18 months each. Six students were acquitted because of insufficient identification, and 10 others are awaiting trial.

The sentences have been described by both Arabs and Israeli authorities as the toughest ever imposed for throwing stones and taking part in a disturbance in the West Bank. They apparently reflect a decision by Israeli authorities to resort to longer prison terms in an effort to halt the frequent outbreaks of stone-throwing in the territory.

"Previous punishments did not achieve the goal," Col. Amnon Straschlow, president of the Ramallah Military Court, said in sentencing eight of the students yesterday. "It is the duty of the court to provide for security in the area and protect those who use the roads."

The July 27 disturbance at Bir Zeit came in reaction to an assault the day before at the Islamic University in Hebron in which two masked gunmen killed three students and injured 33 others. West Bank Arabs and many Israelis say they believe that the assailants were Jewish settlers in the Hebron area, although no identifications or arrests have been made.

According to Army authorities, the Bir Zeit disturbance involved about 200 students who left the campus and began throwing stones at vehicles on the main road through the town. Israeli soldiers, using tear gas and firing live ammunition and rubber bullets, forced the students back onto the campus.

Baramki said two students remain hospitalized from bullet wounds they suffered during the disturbance.

According to Baramki, during negotiations to end the disturbance, the Army promised Bir Zeit officials that students who left the campus on buses for Ramallah would not be arrested. But he said about 70 were arrested by a process of "random selection by the soldiers" as they left.

An Army spokesman denied today that any such promise was made to Bir Zeit officials during the negotiations.

Under the Israeli system of military justice in force in the West Bank, no appeal is possible from the finding of a military court.