An unusual trial involving Citibank, one of its former Far East employes and a mysterious set of ledger books detailing the bank's business with mainland China is scheduled to open in federal court in New York City today.

The former Citibank employe, Robert H. Jones, triggered the legal proceedings when he filed suit against the bank for wrongful dismissal in 1976.

Jones, according to court records, had been a management trainee in international banking from June, 1975, to July, 1976. But on May 10, 1976, he was notified by the bank that he was going to be let go.

But sometime after his notice of dismissal was presented, Jones "removed a number of materials from defendant Citibank's files, including certain original record books of account known to plaintiff as 'Shanghai Record Books Nos. I, II, and III,'" the bank's attorneys said in their filings.

According to the bank's lawyers, Jones adimitted taking the documents in a deposition ordered sealed by the court.

The bank filing says the bank's Shanghai records pertain "to its business and/or commercial relations with the People's Republic of China and the Chinese people."

Besides the Shanghai records, the bank alleges, Jones also took "various confidential memoranda and opinion letters (or copies thereof) written by other employes or agents of defendant Citibank, including memoranda sometimes referred to as: (a) the Bradley memo; (b) the Elkus memo; (c) the Wilson memo; and (d) the Shearman and Sterling memo."

Citibank contends the records belong to the bank, and has filed a countersuit in an attempt to have them recovered. On at least one occasion, U.S. District Court Judge Leonard B. Sand has ordered Jones to turn over the documents. But he has not yet done so.

Citibank officials have not commented on the case, and were not able to identify any of the names associated with the memos. Shearman and Sterling are the bank's law firm.

Attorney John Lewis, representing Citibank, refused to comment at all on the case.

The bank, in its filings, calls the Shanghai books "unique chattels in that they are original bank records." Citibank also contends that Jones violated the terms of his employment by keeping the records.

Although it is unclear what the Shanghai records hold, bank sources say the records could reflect many facets of the bank's operations that could embarrass some depositors or bank officials.