The present disclosure is related to a system for regenerating a DPF and a method thereof. The system for regenerating a DPF during operation of an engine-powered forklift that includes the DPF for collecting particulate matter form exhaust gas discharged from an engine to an exhaust path includes: an engine control unit for controlling operation of the engine; an electro-hydraulic pump for discharging a working fluid that generates a hydraulic load; a control unit for determining a state of the forklift when a DPF regeneration request signal is received from the engine control unit, and controlling at least one of the hydraulic load of the electro-hydraulic pump and revolutions per minute of the engine according to the determined state of the forklift; and a diesel oxidation catalyst unit for regenerating the DPF according to the control of the control unit. According to one or more embodiments of the present invention, it is possible to regenerate a DPF in an engine-powered forklift without periodic forced regeneration of the DPF during operation of the engine-powered forklift, by controlling at least one of a load of an electro-hydraulic pump and an engine speed of an engine. Accordingly, the performance of works may be improved, and the safety may be ensured in the engine-powered forklift.