Max Offenberg, 89, a retired builder, realtor and financier, died Tuesday at Georgetown University Hospital. He had suffered from a heart ailment.

Mr. Offenberg and his wife, Lillian, who died about a year ago, had established the Offenberg Foundation, mostly to assist young people. It is administered by Adas Israel Congregation. They also had supported several hospitals and other institutions here.

Mr. Offenberg was born in New York City. He came here with his family as a boy. He started in business as a tire dealer and then became a Ford automobile dealer.

Eventually he started buying land and developing it, putting up mostly apartment buildings. He was at one time associated with the KLO realty company and the Consum realty company. He retired shortly after World War II.

In the late 1950s, Mr. Offenberg and Constas Gus Basiliko, a Washington real estate man, were convicted in Montgomery County of conspiring to defraud the Maryland State Roads Commission by jacking up land values in the path of a new Rte. 240. The case was widely publicized. Mr. Offenberg paid a $2,000 fine.

An Army veteran of World War I, Mr. Offenberg was active in the Jewish War Veterans. He was a founding member of the Young Men's Hebrew Association, the Benjamin Franklin Masonic Lodge and the Amity Club. He belonged to Woodmont County Club.

There are no immediate survivors.