A 25-year-old Southeast Washington man was sentenced by a Montgomery County Circuit Court judge yesterday to two life sentences, plus 65 years in prison, for the killing of a police officer and a security guard during a 1981 robbery at the W. Bell and Co. discount store in White Oak.

Judge William M. Cave, who had the option of sentencing Curtis Wayne Monroe to death in the gas chamber, said in announcing the lesser sentence that he was impressed by Monroe's efforts to further his education and to seek religious counseling during his stay in the county detention center.

This case "is not one in which the death penalty should be imposed," said Cave, who had sentenced Monroe's accomplice, James Arthur Calhoun, to the gas chamber last November.

"I don't have the power I wish I did and that would be to exchange your life for the lives you have taken," Cave added. "You have forfeited any right you might have had to ever again be a part of society. I hereby sentence you to prison . . . for the rest of your natural life."

The judge ruled that Monroe should never be paroled. Persons sentenced to life may normally apply for parole after 15 years.

Barry Helfand, Monroe's attorney, said he will appeal the decision.

Monroe was convicted of nine charges last June in the March 27, 1981, slayings of police officer Phillip C. Metz, 33, and security guard David Myers, 30. He waived sentencing by the jury that convicted him.

Metz and Myers were investigating a burglary alarm when a gunman, identified in testimony as Calhoun, grabbed Metz and shot him while another man, later identified as Monroe, jumped out and fired.