MEN, TOO, ARE VICTIMS of sex discrimination. Just the other day, the Supreme Court held unconstitutional a part of the Social Security law providing benefits to surviving spouses of deceased wage-earners. The case brought by a man, and the winners are male surviving spouses, who must now be treated as well as their female counterparts have been treated for years.

The case involved the widower of a New York secretary who had paid Social Security taxes for almost 25 years before her death. Under the law, he was entitled to a widower's benefit only if he could prove that she had contributed 75 per cent or more of their family income. But if he had been the spouse who paid the taxes and died, she would have been entitled to a widow's benefit automatically. That distinction, based solely on sex, reflects an unrealistic view of the role each sex has in society. It ought not to be tolerated under the constitutional concept of equal protection.

Justices Brennan, White, Marshall and Powell saw the case in that framework. They found unconstitutional discrimination against the female wage-earner: her taxes had provided less security for her family than those paid by males. The fifth vote needed to declare the provision unconstitutional came from Justice Stevens, who thought the discrimination was against the male beneficiary. What baffles us is the view of the other Justices, led by Justice Rehnquist, who said the discrimination was justified by administrative convenience and by what boils down to the idea that it is constitutional for government to treat women better than it treats men. That view - and the opposite one that government can treat women worse than it treats men - underlines the need for ratification of the Equal Rights Amendment, we might add.

The decision cries out for an immediate response by Congress. If it decides to make women, like men, prove the need for a survivor's benefit, Social Security spending is likely to be reduced by more than a half billion dollars a year. If it decides to give men, like women, the benefit automatically, that spending will increase substantially. But this is not the only provision of the Social Security law that is predicated on sex distinctions. Justice Brennan ticked off others in his opinion as if to send a message across Capitol Hill. Congress ought to heed that message and wipe out those distinctions now. That would save the years of litigation - lawyers' fees and judges' time - which will otherwise be required before the Court can wipe them out itself.