An exhaust gas purification system for an internal combustion engine comprising: an exhaust gas purification apparatus provided in an exhaust passage of the internal combustion engine; a burner provided in the exhaust passage upstream of said exhaust gas purification apparatus and having a burner combustion chamber in which flame is produced, a secondary air supply part (12, 23) that supplies secondary air into the interior of said burner combustion chamber, a fuel injection part that injects fuel into the interior of said burner combustion chamber, and an ignition part that ignites a mixture of secondary air and fuel formed in said burner combustion chamber; characterized by a determination unit that determines whether or not the flow rate of exhaust gas is equal to or lower than a predetermined flow rate; and a burner control unit that causes said burner to produce flame that extends from the interior of said burner combustion chamber to the interior of the exhaust passage upstream of said exhaust gas purification apparatus when it is determined by said determination unit that the flow rate of exhaust gas is equal to or lower than said predetermined flow rate and causes said burner to make the size of the flame produced in the interior of the exhaust passage smaller than when it is determined that the flow rate of exhaust gas is equal to or lower than said predetermined flow rate or to produce flame only in the interior of said burner combustion chamber when it is determined by said determination unit that the flow rate of exhaust gas is higher than said predetermined flow rate, at the time of raising the temperature of said exhaust gas purification apparatus. an exhaust gas purification apparatus provided in an exhaust passage of the internal combustion engine; a burner provided in the exhaust passage upstream of said exhaust gas purification apparatus and having a burner combustion chamber in which flame is produced, a secondary air supply part (12, 23) that supplies secondary air into the interior of said burner combustion chamber, a fuel injection part that injects fuel into the interior of said burner combustion chamber, and an ignition part that ignites a mixture of secondary air and fuel formed in said burner combustion chamber; characterized by a determination unit that determines whether or not the flow rate of exhaust gas is equal to or lower than a predetermined flow rate; and a burner control unit that causes said burner to produce flame that extends from the interior of said burner combustion chamber to the interior of the exhaust passage upstream of said exhaust gas purification apparatus when it is determined by said determination unit that the flow rate of exhaust gas is equal to or lower than said predetermined flow rate and causes said burner to make the size of the flame produced in the interior of the exhaust passage smaller than when it is determined that the flow rate of exhaust gas is equal to or lower than said predetermined flow rate or to produce flame only in the interior of said burner combustion chamber when it is determined by said determination unit that the flow rate of exhaust gas is higher than said predetermined flow rate, at the time of raising the temperature of said exhaust gas purification apparatus.