Seymour R. Thaler (August 31, 1919 – February 5, 1976) was an American lawyer and politician from New York.
He won a seat on the New York Supreme Court in 1971, but never heard a case as a result of his 1972 conviction for dealing in stolen Treasury securities.
Thaler first won election to the Senate in 1958, defeating incumbent Irwin Pakula in the 7th district from Queens.
In 1962, Thaler ran as an independent candidate in a special election to replace Lester Holtzman, who had resigned to take a judgeship on the New York Supreme Court.
While in prison, he filed a $52.5 million Federal lawsuit against the Second National Bank Of New Haven alleging that the bank's negligent failure to inform him that the securities were stolen cost him his office, law license and resulted in public scorn.
The judge Jon O. Newman dismissed the case, comparing Thaler to a child who murdered his parents and sought pity as an orphan.