Five states and four members of Congress yesterday sued the Agriculture Department and the Office of Management and Budget, charging that they have failed to spend the full amount that Congress appropriated this year for the Supplemental Food Program for Women, Infants and Children (WIC).

Michael Lemov, executive director of the Food Research and Action Center (FRAC), which filed the suit on behalf of the complainants in U.S. District Court here, said Congress had ordered USDA to spend a total of $1.5 billion this year. However, he said, at the rate the department is allocating the money to the states, it will spend $80 million less than that.

Lemov said the failure to allocate the full amount means that states have been unable to feed the 3.08 million people that Congess had intended. "The WIC program is our nation's front-line defense against low birth weight and infant mortality," he said.

Robert Greenstein, director of the Center for Budget and Policy Priorities, said that a survey by his group showed that 10 states already had begun to cut their caseloads or food allocations and that it appeared that by year's end, 250,000 cases would have to be dropped.

Congress voted $1.5 billion for the WIC program in fiscal 1985, but said the administration could decide when to use the last $246 million. The administration requested $169.3 million of that amount.

FRAC said that Congress had specifically required that the money be allocated during the first part of the year as if the full $1.5 billion would be spent.

The plaintiffs in the suit are Texas, New Mexico, Arkansas, New York and Maine, and Reps. Augustus F. Hawkins (D-Calif.), George Miller (D-Calif.), Matthew F. McHugh (D-N.Y.) and William B. Richardson (D-N.M.).

OMB spokesman Edwin L. Dale Jr. said that the administration believes it is following the law.