Firefighters arrived just before 10pm to find lots of smoke and flames coming from the house.
Crews found the home on North Braeswood near the West Loop South was boarded up from last week's fire.
The homeowner told investigators they drove by earlier in the evening, noticed the front door was open and left. When they returned, there was a fire burning inside.
Crews said the fire was contained to a single room and was put out. No one appeared to be inside the home at the time of the fire.
Meantime, another fire was set in a trash dumpster a few blocks away. That fire combined with the house fire has authorities looking into the possibility of an arsonist in the area.