A hybrid wood-burning fireplace assembly configured for burning wood-based fuel, wherein the burning generates combustion exhaust. The assembly comprising a fire box having an interior area, a baffle in the interior area defining lower and upper combustion chambers relative to the baffle. The upper combustion chamber has an upper exhaust passageway between baffle and the top portion of the firebox. A secondary combustion airway has air outlets in the firebox that direct the secondary combustion air adjacent to the baffle to mix with the exhaust for non-catalytic secondary combustion of the exhaust before the exhaust flows through the upper exhaust passageway. A catalytic combustion unit is positioned above the baffle and across the upper exhaust passageway, whereby the exhaust will pass through the catalytic combustion unit after the non-catalytic secondary combustion of the exhaust and before the exhaust exits the upper combustion chamber through the upper exhaust passageway.