A printing system comprising: a printing unit configured to perform printing on a sheet; a conveyance mechanism that includes a printing path for guiding the sheet to a printing position of the printing unit and a reverse path for reversing the sheet which passes through the printing path and guiding the reversed sheet to the printing position once again; and a control unit configured to perform double-side printing processing; a calculation unit configured to calculate an occurrence probability of sheet jamming; and a first informing unit configured to inform a user, characterized in that the control unit is configured to perform the double-side printing processing using any one of a plurality of methods whose maximum numbers of sheets existing in the conveyance mechanism at the same time are different from each other, the printing system comprises a selection unit configured to select any one of the plurality of methods according to an instruction from a user, wherein the control unit performs the double-side printing processing in accordance with the method selected by the selection unit, the calculation unit is configured to calculate a total jamming occurrence probability, which is an occurrence probability of jamming which occurs in the printing system including the printing path and the reverse path, for each of the plurality of methods, respectively, and to calculate a reversing jamming occurrence probability, which is the probability that a jamming occurs in the reverse path, for each of the plurality of methods, respectively, and the first informing unit is configured to inform the user about the total jamming occurrence probability calculated by the calculation unit for each of the plurality of methods, respectively, and about the reversing jamming occurrence probability calculated by the calculation unit for each of the plurality of methods, respectively, the control unit can perform double-side printing processing depending on a non-reversing method in which the reverse path is not used, and when the reversing jamming occurrence probability of a method selected by the selection unit according to the instruction from the user is higher than an upper limit, the method is switched into the non-reversing method. a printing unit configured to perform printing on a sheet; a conveyance mechanism that includes a printing path for guiding the sheet to a printing position of the printing unit and a reverse path for reversing the sheet which passes through the printing path and guiding the reversed sheet to the printing position once again; and a control unit configured to perform double-side printing processing; a calculation unit configured to calculate an occurrence probability of sheet jamming; and a first informing unit configured to inform a user, characterized in that the control unit is configured to perform the double-side printing processing using any one of a plurality of methods whose maximum numbers of sheets existing in the conveyance mechanism at the same time are different from each other, the printing system comprises a selection unit configured to select any one of the plurality of methods according to an instruction from a user, wherein the control unit performs the double-side printing processing in accordance with the method selected by the selection unit, the calculation unit is configured to calculate a total jamming occurrence probability, which is an occurrence probability of jamming which occurs in the printing system including the printing path and the reverse path, for each of the plurality of methods, respectively, and to calculate a reversing jamming occurrence probability, which is the probability that a jamming occurs in the reverse path, for each of the plurality of methods, respectively, and the first informing unit is configured to inform the user about the total jamming occurrence probability calculated by the calculation unit for each of the plurality of methods, respectively, and about the reversing jamming occurrence probability calculated by the calculation unit for each of the plurality of methods, respectively, the control unit can perform double-side printing processing depending on a non-reversing method in which the reverse path is not used, and when the reversing jamming occurrence probability of a method selected by the selection unit according to the instruction from the user is higher than an upper limit, the method is switched into the non-reversing method.