DETROIT — Shareholders of General Motors on Tuesday rejected proposals by a dissident investor to replace three company directors and split the automaker’s stock into two classes.

The proposals, by the hedge fund Greenlight Capital, which owns a 3.6 percent stake in G.M., were aimed at bolstering the sagging value of the automaker’s stock.

G.M.’s chief executive, Mary T. Barra, and its board opposed the moves, which included creating two classes of stock — one paying a dividend and a second one tracking earnings growth.

“We determined the Greenlight proposal was not in the best interests of our shareholders,” Ms. Barra said at the company’s annual meeting in Detroit.

The company said Greenlight’s dual-stock proposal was defeated with more than 91 percent of the votes cast against it.

Greenlight’s president, David Einhorn, did not attend the meeting. He has criticized what he has termed “uninspired” leadership at G.M., and proposed to replace three of the 11 board members with a slate nominated by Greenlight.

But the proposals lost by substantial margins — although G.M.’s stock price has barely increased in value since its post-bankruptcy stock offering in 2010.

Instead, shareholders showed broad support for the strategic direction of the company under Ms. Barra, who became chief executive three years ago.

G.M., the nation’s largest automaker, has earned more than $40 billion in profit since it emerged from its government-sponsored bankruptcy in 2009.

In the last year, the company has made big moves by agreeing to sell its auto operations in Europe, as well as exiting several international markets, including Russia, India and South Africa.

Ms. Barra has said those businesses did not meet G.M.’s targets for profit margins and were not integral to its effort to transform the company into a leaner, more technology-driven enterprise.

She acknowledged the frustration of investors, but Ms. Barra said the company would continue to take “decisive actions” to unlock value for shareholders.

“We have to keep earning our way,” she said.