A blog report by security expert Brian Krebs has suggested that several of its stores in north-east America have been affected by a breach.
If correct, it would make Staples the latest in an increasingly long line of US retailers to have been targeted by hackers.
The US government has called for a swift move to chip-and-pin technology.
Stores are gradually making the move from using magnetic strip payment cards - the most common form of payment in the US - to the more secure chip-and-pin.
Many are now rushing through the changes following a series of high-profile breaches where hackers have put card-stealing malware on cash registers.
Staples, it seems, could be the latest victim.
Mr Krebs, a US security expert who has written widely on retail data breaches, blogged that bank officials were investigating breaches at Staples stores in New York, Pennsylvania and New Jersey.
"Multiple banks say they have identified a pattern of credit and debit card fraud suggesting that several Staples Inc. office supply locations in north-eastern United States are currently dealing with a data breach," Mr Krebs wrote.
Staples said it was investigating the matter.
"Staples is in the process of investigating a potential issue involving credit card data and has contacted law enforcement," company spokesman Mark Cautela said in a statement.
Earlier this month, Sears Holdings said it had discovered that point-of-sale registers at its Kmart stores had been compromised by malicious software.
Fast-food chain Dairy Queen also reported that malware had been installed on cash registers in nearly 400 of its stores.
And, at the end of last year, Target suffered a massive data breach which affected up to 70 million customers.
It has led the US government to call for the widespread adoption of chip-and-pin technology.
"With over 100 million Americans falling victim to data breaches over the last year, and millions suffering from credit card fraud and identity crimes, there is a need to act and move our economy toward secure technologies that better secure transactions and safeguard sensitive data," the Obama administration said in a press release.
Office supply superstore Staples is investigating possible payment card data thefts, according to reports.