The Massachusetts Department of Housing and Community Development has awarded a $3.9 million grant to the One Greenway mixed-income housing project in Boston’s Chinatown neighborhood.

The project, sponsored by the New Boston Fund and Asian Community Development Corp., will set aside 46 of 51 condo units in the South Building for families earning at or below 80 percent of the median income in the area. Construction is scheduled to begin in mid-2015.

The North Building broke ground last fall and will include 217 market-rate rentals and 95 affordable rentals. The project also includes 135 garage parking spaces, approximately 8,500 square feet of retail and community space and a new pedestrian connection between Hudson Street and Albany Street.