TEHRAN--As the new Iranian civilian government encountered problems with military and political leaders, 50-60 people died yesterday in demonstrations demanding the abdication of Shah Mohammad Reza Pahlavi.

Prime Minister Shahpour Bakhtiar delayed plans to present his cabinet to Parliament until Thursday, while a key general reportedly walked out of the cabinet, and government officials were said to have tried to block Bakhtiar ministers from their offices.

The Shah will await a vote of confidence from the Parliament Saturday before possibly departing on a trip abroad, sources in Iran said. According to the sources, the Shah will appoint a regency council to exercise power in his absence.

Bakhtiar, expected to be appointed to the council, was the second most powerful man in the opposition National Front, until he was repudiated for accepting the prime minister's post.

In an effort to enlist the cooperation of the military, Bakhtiar met Thursday with General Fereidum Jam, to whom he had offered the supervision of Iran's 430,000-man military establishment. The general rejected the appointment, after reportedly disagreeing with plans to restructure the military.

Meanwhile, religious leader Ayatullah Khomeini called for a second "national day of mourning" to commemorate the deaths of more than 1500 persons in anti-Shah protests this year. The government belatedly endorsed the call.

Small groups of protesters roamed through downtown Tehran setting fires. Officials said three people were killed when troops fired on a mob and set fire to a government-owned department store.

However, Ayatullah Shariatmadari, the senior Shiite Moslem leader in Iran, led a mass march through the streets of Jom, about a hundred miles south of Tehran, where there were no reports of trouble.