An exhaust gas purifying system includes an exhaust gas purifying apparatus provided with a gas inlet side connected to an inlet pipe and a gas outlet side connected to an exhaust pipe. A holding sealing material of the exhaust gas purifying apparatus has a first side face and a second side face. The first side face is positioned on the gas outlet side and has a first slanting face formed on the first side face. The first slanting face has a first inside end point and a first outside end point. The first inside end point is positioned between the gas inlet side and the first outside end point. The first slanting face extends from the first inside end point to the first outside end point and is tilted relative to an end face of an exhaust gas treating body of the exhaust gas purifying apparatus.