On American college campuses, Shah Mohammad Reza Pahlavi may not be missed ideologically, but finalcially his ouster from the throne of Iran has left substantial gaps in academic budgets.

And, ironically, the people most immediately affected are 50,000 Iranian students in this country, many of whom spent the last several years demonstrating against the monarch with shouts of "Death to the Shan." Iranian funds, both from the government and from their families, have been cut off.

Although this was a short-term loss for universities and colleges that allowed the students to postpone payment for tuition, housing and board, a long-range problem is the loss of revenue to American institutions.

Oil money from Iran had provided a new source of income at a critical time, as funding from froundations was drying up. In turn, Middle East studies prospered.

Some institutions, such as Princeton, obtained funds from Iran when they first expanded their Mideast studies. At Princeton, Chairman John Marks said his Department of Near East Studies received a grant of $400,000 from the Pahlavi Foundation in 1969 toward an endowment that has reached about $1 million. The foundation once dispensed vast sums from contributions by the Shah and his family and by the Iranian government.

Other gifts to the department's endowment included $100,000 from Iranian Oil Co. and $100,000 from American corporations.

With the aid of its endowment, plus funds from its regular budget, Princeton has maintained one of the country's more auspicious programs in Mideast studies. Fifteen faculty members, including three specialists on Iran, are teaching Mideast subjects to 44 graduate students and 600 undergraduates.

Other institutions, particularly those operating large exchange programs with Iranian universities, have encountered serious financial difficulties since the revolution that toppled the shah.

The University of Illinois Asian Center established a joint research unit with the University of Tehran 10 years ago and, since 1970, had conducted an English-language teaching program in Iran. Prof. Marvin Weinbaum, coordinator of the research unit, said in a telephone interview that 25 Illinois students who were studying in Iran returned early this year when Iranian payments ceased.

A University of Illinois faculty exchange with the University of Tehran and Arye Mehr University fell victim to a strike by the teaching staff of Arya Mehr last summer. Then the University of Tehran failed to open at the beginning of the academic year, and Weinbaum said the exchange had to be suspended and airfare home paid for the Illinois professors.

No payments from the two Iranian universities were made during the 1978-79 academic year and, with both still closed, student and faculty exchanges are in limbo.

One of the biggest Iranian studies programs in the United States was at the University of Utah, which created with the University of Tehran in 1975 a division of Iranian studies in Utah's Middle East Center.

With $100,000 a year promised by the government-financed Tehran institution, Utah hired professors of history, anthropology and archeology. There were 26 graduate students and six undergraduates enrolled in the division at the opening of the current academic year.

Tehran met its obligations for 1977-78 but has made no payment in this academic year, according to University of Utah officials.

Under an exchange program that was to provide transportation and $3,000 a year subsistence, one Utah graduate student flew to Tehran in September. After he arrived, he received no money. As the University of Tehran remained closed and unrest increased in the capital, he paid his own way home in February. He was reimbursed by the University of Utah.

Another American student nominated for the exchange never left the United States because his ticket failed to arrive, Dr. Khosrow Mostofi of the University of Utah said, but Utah paid the expenses of two Iranians for a year in Salt Lake City.

"We are going on the promise of an institutional commitment, regardless of the government in power," Mostofi said. "If they don't fulfill their commitment, we'll still do everything possible to keep our end of the bargain."