Roche Bros. is coming to Waltham, and for some residents that means grocery shopping will be just a short walk downstairs from their kitchen.

The Wellesley-based supermarket chain will open one of its smaller-format Brothers Marketplace stores next spring in the Merc at Moody and Main apartment building in downtown Waltham.

It’s the latest foray by Roche Bros. into more densely populated urban markets in Greater Boston, and one of a growing number of grocery stores slated for the ground floors of housing developments.

The store is the company’s third Brothers Marketplace — they’re already open in Weston and Medfield — and at 8,500 square feet will be less than one-third the size of a typical Roche Bros. supermarket.

The Waltham store will be full-service, said Paul McGillivray, vice president of customer experience, but the offerings will skew toward produce, meat, seafood, and prepared foods for nearby residents who are likely to make smaller, more-frequent food purchases.

“It’s designed to create a more convenient shopping experience,’’ McGillivray said. “It’s really geared to the way we see customers living today.’’

The store will sit on a corner of Main Street, on the ground floor of a new 269-unit apartment building next to a commuter rail stop. Peter Standish, head of development at Northland Investment Corp., which built the Merc project, considers the store an amenity for residents of the building and a draw for people who live and work nearby.

“It’s an extension of our amenities and what we’re trying to create here,’’ Standish said.

“We view this as a real urban-type location, someplace where residents can walk to restaurants, a movie theater, all these great conveniences. To have a really high-quality grocer in our building is ideal.’’

Tim Logan can be reached at tim.logan@globe.com. Follow him on Twitter at @bytimlogan.