NEW YORK (AP) _ Stockbrokers regularly treat potential female customers less seriously than men, belittling their concerns and spending less time explaining investments, according to a magazine survey.

The survey in the June issue of Money found brokers do treat women with more courtesy than men.

But it found they asked men more probing questions about their investments and attempted to sign men as customers more frequently than women.

''Brokers may think that women have less investing experience and will simply be confused by explanations,'' said Mary Malgoire, a financial planner in Bethesda, Md.

The magazine's surveyor, Barry Leeds & Associates of New York, visited 50 retail brokerage offices in Chicago and Los Angeles.

The company sent two groups of testers - one between the ages of 30 and 45, and the other 50 to 65 years old - to offices of Dean Witter, Edward D. Jones, Merrill Lynch, Shearson Lehman, Kemper Securities and Sutro & Co.

The younger testers said they had $25,000 to invest, while the older testers said they had $50,000.

Many brokerage firms would not comment on the survey, the magazine said. But a Merrill Lynch spokesman said, ''In our surveys, we have found no difference in the quality of service offered to men and women.''