The presidential commission studying October's stock market collapse plans to submit its final report to President Reagan today, but the White House yesterday played down its significance in shaping any immediate market reforms.

With the dollar and stock prices making strong gains in early 1988 trading, the White House was eager to avoid anything that could adversely affect investor sentiment, administration sources said.

White House spokesman Marlin Fitzwater said the study, prepared by the presidential commission headed by Dillon Read investment banker Nicholas F. Brady, is only one of several reports on the market collapse. He said that before the president reaches a final judgment on possible Wall Street reforms, considerable weight would be given to other reports not yet completed, such as studies by the Securities and Exchange Commission and the Commodity Futures Trading Commission.

By deemphasizing the study, the White House keeps all of its policy options open while diminishing a controversy that could arise from recommendations in the study, such as a proposal that could lead to limits on the maximum daily movement of stock and stock index futures prices.

Sources familiar with the Brady Commission report said its theme is that regulation of stocks and stock index futures ought to be "unified." Sources said, for example, that the study concludes that if daily price limits are imposed on stock index futures, they ought to be imposed on stocks as well.

However, sources said the report stops short of recommending how broad such price limits ought to be or how they should be implemented. Temporary price limits were imposed on stock index futures after the stock market collapse in October.

Under the unified regulatory theme, sources said, the report also proposes that gaps resulting from the SEC's regulation of stocks and the CFTC's regulation of stock index futures be closed by putting another regulatory body in charge of coordination. Such a body could have the authority to take steps, such as halting trading in both markets, to minimize the risk of a free fall in prices during a panic, sources said.

Stock index futures give investors the opportunity to speculate on the future movement of broad stock market averages, such as the Standard & Poor's 500. The close relationship between stock and stock index futures trading in the market collapse has prompted calls on Wall Street and in Washington for better regulatory coordination.

When the Chicago Mercantile Exchange and the New York Stock Exchange recently released their studies of the market collapse, congressional sources said the studies represented the special interests of the exchanges, adding that the Brady Commission report would be more objective and significant. But Fitzwater would not put the Reagan administration's endorsement on policy recommendations in the Brady report yesterday.

"I wouldn't anticipate near-term actions ... because of the ongoing nature of the other studies and we want to wait until they are all in," Fitzwater said. " ... We will have to look at all the data. The Treasury will take a look at this material {as will} other financial authorities. But you don't move precipitously."

Fitzwater declined to comment on conflicting reports yesterday in The Wall Street Journal and The Los Angeles Times concerning the recommendations in the Brady report. Administration officials said the Journal description was more accurate. The L.A. Times dispatch was included in some editions of Thursday's Washington Post.

Any limits on the maximum daily rise or fall in stock prices and any resulting trading halts could affect traders and trading strategies in numerous ways.

The New York Stock Exchange is opposed to any stock price limits. Bear Stearns brokerage chief Alan C. (Ace) Greenberg, calling himself "a great believer in the free market," said recently of the idea of price limits, "I think it stinks."

But Kidder Peabody president Max C. Chapman said in an interview yesterday he supports the concept of price limits for stocks and bonds. "The basic premise of price limits is to give the market time to look and determine real value," Chapman said. "The basic concept is one I continue to endorse."

One administration official, asked recently about proposals to limit daily price swings in stocks and stock index futures, indicated that the administration is open to the idea. "If the evidence shows that things can happen so fast {in the markets} that it overwhelms {the markets'} efficiency, then we have to adopt the structure," the official said.

The interaction between the stock and futures markets has raised questions about whether both should be regulated by a single entity. But sources said the study instead proposes that the SEC and CFTC continue their oversight of stocks and futures, respectively, and that another regulatory body be charged with coordinating regulation.

There has been considerable discussion about the Federal Reserve assuming the role of stock and futures markets coordinator and watchdog, but sources said the Fed is not interested in increasing its authority over the markets.

Sources said other proposals in the Brady Commission report concern processing of stock trades and the minimum cash requirements, or margins, for the purchase of stocks and stock index futures.

Congressional action could be needed to enact some of the proposals in the Brady study. The Senate Banking Committee has scheduled hearings on the stock market studies next month.

Staff writers Paul Blustein and John M. Berry contributed to this report.