By ANDREW JACOBS

BEIJING — It is hard to know exactly which transgression propelled Xia Yeliang, an accomplished Peking University economist, from opinionated irritant to a marked enemy of the ruling Communist Party. There was his 2009 public letter that ridiculed the technical school degree held by the nation’s propaganda minister and the interview he gave last year to Radio Free Asia, describing China as a “Communist one-party dictatorship.”

But Professor Xia, a former teenage Red Guard turned free-market advocate, says he most likely crossed a line last year when he posted an online jeremiad calling on Chinese intellectuals to gather in public squares to debate political reform. “That seemed to really upset school administrators,” he said recently. It also apparently upset powerful figures in the Communist Party.

In the coming weeks, Professor Xia says, he is likely to be dismissed from his teaching post at Peking University, one of the nation’s most prestigious schools, a move he and others say reflects the government’s determination to control intellectual discourse at the nation’s leading educational institutions.

Administrators have told him his fate will be decided by a panel of his peers, a feint he says is intended to head off criticism that his punishment is politically driven. “I’m not terribly optimistic for my future,” said Professor Xia, 53, an animated man whose classroom lectures on macroeconomics are often flecked with colorful jabs at the party.

The effort to silence Professor Xia has thrown into sharp relief the challenges facing elite colleges and universities like Peking University, caught between political controls at home and their ambitions to gain international respect as grand centers of learning. In recent years, the university has waged a muscular and well-financed effort to raise its global profile through partnerships and exchanges with some of the world’s top institutions.

Last year, Stanford University opened a $7 million research center on the Peking University campus, and a growing list of other colleges and universities, including Cornell, Yale and the London School of Economics, have established dual-degree programs or enhanced academic collaboration.

Zhang Qianfan, a law professor at Peking University, said punishing Professor Xia would most likely harm the university’s efforts at elevating its stature abroad. “It would send out a message that the university is not able to resist political interference and is unable to separate politics from academics, which is a basic requirement for those trying to carry out decent academic work,” he said.

The campaign to silence Professor Xia has not gone unnoticed overseas. The Committee of Concerned Scientists has taken up his plight, and last month more than 130 faculty members at Wellesley College signed an open letter calling on administrators to reconsider their partnership with Peking University should he be fired.

Neither the office of Peking University’s president nor the economics department responded to interview requests.

A prolific author and once a frequent commentator on Chinese news programs, Professor Xia first drew the ire of university officials in 2008, when he was among the first to add his name to a manifesto that demanded an end to single-party rule. The petition, called Charter 08, drew 300 signers and deeply unnerved top party leaders, prompting the prosecution of its primary author, Liu Xiaobo, the Nobel laureate who is serving an 11-year sentence for subversion. A year later, Professor Xia posted his open letter to China’s propaganda chief comparing his department’s efforts to that of the Nazis.

Since then, Professor Xia says, he has endured bouts of house arrest or found himself trailed by state security agents. But he says he has been largely left alone. In recent years, university administrators have permitted him to spend long stretches abroad as a visiting scholar, including at Stanford until September.

But last year, after he posted his online letter calling for a public discussion of political reform, university administrators demanded that he return to China and then warned him to tone down his antigovernment invective.

Since then, he has continued to criticize the Communist Party while advocating Western-style democracy through microblog postings that are often deleted as soon as they go up. (His current microblog on Sina Weibo is called “Xiayeliang the Ninth” because the previous eight accounts have been shut down.) “I’ve never advocated revolution,” he said. “Just peaceful change.”