Police and the Happy-Valley-Goose Bay Fire Department responded to the fire Motherwood Hardware on Kelland Drive around 3 a.m.
On arrival, the building was engulfed in flames and could not be saved.
Police are being assisted in the investigation by Fire and Emergency Services.
Anyone who may have information is asked to please call the Happy Valley-Goose Bay RCMP at (709) 896-3383. To remain anonymous,contact Crime Stoppers toll free at 1-800-222-TIPS (8477), text TIP190 + your message to 'CRIMES' (274637), or submit a webtip at www.nlcrimestoppers.com.