Ryohin Keikaku said Muji aims to close unprofitable stores and renegotiate rents in the United States, where its 18 stores have been closed since mid-March due to the pandemic.
The outbreak has inflicted widespread financial pain on global retailers, leading many such as J. Crew Group and Brooks Brothers to file for bankruptcy protection.
Ryohin Keikaku said the U.S. filing will not affect its operations in other markets.
But the business has also been hit by store closures and weak consumer spending in its main market, Japan.
Separately on Friday, Ryohin Keikaku reported an operating loss of 2.9 billion yen ($27.2 million) for the quarter through May.
($1 = 106.8300 yen)
(Reporting by Ritsuko Ando; Editing by Richard Pullin)