Paul May, 83, a former official of the Treasury Department and the Internal Revenue Service who later became a private investment counsellor, died Saturday at the Carroll Manor nursing center in Hyattsville of complications following a stroke. A resident of Washington most of his life, he has been at Carroll Manor for a month.

Mr. May, an accountant by training and profession, worked at Treasury and the IRS from 1920 until the early 1950s. He specialized in helping prepare criminal prosecutions involving tax fraud. He then became an investment counsellor and was appointed the executor of a number of estates. He continued this work until the late 1970s. Apart from his family and his work, he was active in the Catholic Church and received a Papal honor for his efforts in its behalf.

A third-generation Washingtonian, Mr. May attended St. John's College and Gonzaga high schools and graduated from Mount St. Mary's High. He also graduated from Mount St. Mary's College in Emmitsburg, Md. He began his career at Treasury after World War I service in the Navy. He later earned a degree in business administration from American University.

At Treasury, Mr. May received the department's Albert Gallatin Award.

For 30 years, Mr. May was treasurer of the Catholic Home for Aged Ladies, which was started by his mother and which was later taken over by the church and became part of the Carroll Manor facility. He also was a financial adviser to the Sisters of the Convent of Perpetual Adoration.

He was a member of the board of the Merrick Boys Camp, which is sponsored by the Christ Child Society, a member of the John Carroll Society, the First Friday Club, the parish of the Shrine of the Most Blessed Sacrament Catholic and its Holy Name Society, and of the Knights of Columbus. Pope John XXIII bestowed on him the Pro Ecclesia et Pontifice Medal.

Mr. May also was a member of the Columbia Historical Society. He was golfer and member of the Columbia Country Club. He lived in Sherwood Forest from the mid-1960s to the late 1970s, and then returned to Washington. He was a member of the Annapolis Yacht Club.

Survivors include his wife, Olga Ruppert May, to whom he was married for 58 years, of Washington; one daughter, Rose Mary May Splain, of Washington; one brother Albert, of Sherwood Forest; 16 grandchildren, and nine great-grandchildren. A son, Paul May Jr., died in 1979.

The family suggest that expressions of sympathy be in the form of contributions to the Grotto of the Lourdes, c/o Msgr. Hugh Phillips, Emmitsburg, Md., 21727.