The chairman of Suburban Bancorporation, the holding company for Suburban Trust Bank, told shareholders yesterday that the bank will be restructured and organized around product groups.

The reorganization is part of a general new upscale look for the bank, which includes moving its headquarters from Hyattsville to Bethesda, and efforts to develop a new corporate identity, tying the parts of the holding company together more closely.

Chairman Robert F. Tardio characterized the bank's moves as getting ready for the 1980s and 1990s. "We decided that the time to do it was while we were strong, not under pressure," he said.

The restructuring was done with the help of consultants Cresap, McCormick and Paget Inc. The new bank building is going up at the intersection of Democracy Boulevard and Interstate 270 in Montgomery County. "For several years we've been in desparate need for space," said Tardio, who added that the bank company's administrative, executive and lending offices would be moved there from Prince George's County.

About 270 Suburban shareholders attended the annual meeting at the Holiday Inn in Bethesda, near the bank's new president G. J. (Bud) Manderfield, noted that loan charge-offs had increased but that the bank maintained its profitability.

Net loan charge-offs were $8 million in 1980, $4.4 million in 1979 and $1.5 million in 1978, with the increases reflecting in part a more conservative position on loan charge-offs by the bank, he said.

"In 1981, they will remain high. In 1982, they should be significantly lower," Manderfield said.

Suburban's consolidated income before net securities transactions was $4.159 million (88 cents per share) in the first quarter of 1981, up 4.6 percent from $3.975 million (84 cents) in the same quarter last year.

Net interest income for the first quarter increased 2 1/2 percent to $17.872 million from $17.441 million for the first quarter of 1980. Total operating income for the first quarter was $41.577 million, an increase of 15.4 percent from $36.03 million in the same three months a year ago. That growth reflected an increase in income from interest on investment securities, Tardio said.

Other benchmarks were return on average total assets, which was 1.17 percent in the first quarter of 1981 compared with 1.16 percent for the same period in 1980, and total deposits. On March 31 total deposits were $1.28 billion compared with $1.26 billion at the end of 1980. Stockholders' equity rose to $115.5 million for the first quarter of 1981 compared with $113.1 million at the end of 1980.

In answer to questions from shareholders, Tardio said he was making no specific effort to recruit minorities or women for the board of Suburban Bancorp. "I will continue to look for competent people to serve on the board, but there is no automatic entitlement or entre to those boards," said Tardio, who was applauded loudly by the largely white male crowd.

In answer to another shareholder question, Tardio indicated that the bank eventually may close some branches if they don't perform as well as others.