An internal combustion engine exhaust gas purifying system (10) having a continuous regenerating diesel particulate filter system (3) on the exhaust passage (2) of an internal combustion engine (1) is constituted by including collected-quantity estimation means (5A) for estimating the quantity of collected particulate matter in a filter (3b) of the filter system for collecting the particulate matter and maximum-fuel-injection-quantity restricting means (5C) for restricting the maximum fuel injection quantity of the internal combustion engine (1) when the quantity of collected particulate matter estimated by the collected-quantity estimation means (51A) is equal to or more than a predetermined judgment value.Thereby, when the quantity of deposited particulate matter exceeds a predetermined value in the continuous regenerating DPF system (3), it is possible to prevent the continuous regenerating DPF system (1) from deteriorating by restricting the maximum fuel injection quantity of the internal combustion engine (1) and avoiding a great increase of an exhaust gas quantity.