ANNAPOLIS, Md. – A national retail industry trade association filed two lawsuits yesterday, challenging laws in Maryland and New York designed to pressure Wal-Mart Stores to spend more money on health care for its employees.

The Maryland law, the first of its kind in the nation, was enacted January 12 when the Democratic-controlled legislature overrode a veto by Governor Ehrlich, a Republican. The law requires companies with more than 10,000 employees in Maryland to spend at least 8% of payroll on health care or contribute the difference to the state Medicaid fund.

Wal-Mart is the only Maryland company of that size that doesn’t meet the 8% threshold.

The suit was announced in Arlington,Va., by the Retail Industry Leaders Association, which represents companies that operate more than 100,000 stores with more than $1.4 trillion in annual sales.

The association,which also filed a lawsuit challenging a health care law passed in Suffolk County, on Long Island, said the two laws illegally mandate specific health care expenditures and threaten to take away flexibility businesses need to deal with their employees.

“We all agree that access to health care is vital, but these spending mandates will drive away business and discourage job creation,” the chairman of the association and vice chairman and CEO of Best Buy, Brad Anderson, said in a written statement.

The retailing group’s lawyer, Steve Cannon, said Maryland’s law should be tossed because it improperly requires private companies to set certain benefits.

“States may not mandate benefits for private employers,” Mr. Cannon told reporters.

Maryland’s attorney general announced before the vote that the law wouldn’t violate federal benefit rules.

“The attorney general is trying to argue that what is mandated here is neither a plan, a benefit, or a program. I think frankly that’s just simply disingenuous. Of course that’s what this is,” Mr. Cannon said.

Chris Kofinis, communications director for Wake Up Wal-Mart, which lobbied for the bill in Maryland, predicted it will withstand a court challenge.

“The Maryland bill is a responsible piece of legislation that will make sure that large employers live up to their health care responsibilities. Overwhelmingly, Marylanders supported this legislation,” Mr. Kofinis said.

Lawmakers in Suffolk County approved a law last fall that would require large grocery retailers to give workers a health care benefit worth at least $3 an hour. The law applies to companies with at least $1 billion in annual revenue and at least 25,000 square feet of sales space for groceries. Companies are exempt from the rule if they have a collective bargaining agreement, which Wal-Mart does not.

“We are confident that our law will withstand scrutiny,” a Suffolk County attorney, Christine Malafi, said in a statement. “It was drafted to fit within the permissible areas of the law, and we will defend any lawsuit brought against the county as a result of the law.”

Maryland’s predominantly Democratic legislature approved the Wal-Mart bill last year, but it was vetoed over the summer by Governor Ehrlich. After intense lobbying by retailing groups, unions, and Wal-Mart itself, the legislature voted last month by the required three-fifths margin to overcome Mr. Ehrlich’s veto. Union groups have said similar bills are being considered in at least 30 other states.

The president of the Retail Industry Leaders Association, Sandy Kennedy, said the industry hopes the lawsuit dissuades other states from tampering with Wal-Mart’s benefits.

“We certainly hope that the other states … will pause and look at what we’re doing in Maryland and Suffolk County and consider that these are unwise and unlawful laws,” Ms. Kennedy said.

Mr. Ehrlich, Maryland’s governor, said yesterday that the Wal-Mart law was “a ridiculous bill.” He and other Republicans had warned of a lawsuit if it were enacted. “We’re not terribly surprised,” he said. “It’s yet another chapter in a negative story for Maryland.”

Wal-Mart, based in Bentonville,Ark., did not immediately return a phone call seeking comment. Ms. Kennedy said Wal-Mart has a seat on the retailing group’s board, but she said all other board members wanted to file the suit.