A mounting system (10, 150) for mounting an LED element on a board and mounting a lens so as to cover the LED element, the system comprising: one or more board operation execution machines (12, 14, 16, 152) configured to execute an operation with respect to the board; and a control device (100, 102, 104) configured to control the operation of the one or more board operation execution machines (12, 14, 16, 152), wherein the control device (100, 102, 104) includes an LED element mounting unit as a function unit for mounting the LED element in a predetermined mounting position which is a preset position on the board, and a deviation amount acquisition unit as a function unit for acquiring a deviation amount between a mounting position of the LED element mounted by the LED element mounting unit and the predetermined mounting position, characterized in that the control device (100, 102, 104) also includes a first lens mounting unit as a function unit for mounting the lens on the board using a position of the LED element mounted on the board as a reference, when the deviation amount is smaller than a threshold value, and a second lens mounting unit as a function unit for mounting the lens in a preset position on the board, regardless of the position of the LED element mounted on the board, when the deviation amount is equal to or greater than the threshold value. one or more board operation execution machines (12, 14, 16, 152) configured to execute an operation with respect to the board; and a control device (100, 102, 104) configured to control the operation of the one or more board operation execution machines (12, 14, 16, 152), wherein the control device (100, 102, 104) includes an LED element mounting unit as a function unit for mounting the LED element in a predetermined mounting position which is a preset position on the board, and a deviation amount acquisition unit as a function unit for acquiring a deviation amount between a mounting position of the LED element mounted by the LED element mounting unit and the predetermined mounting position, characterized in that an LED element mounting unit as a function unit for mounting the LED element in a predetermined mounting position which is a preset position on the board, and a deviation amount acquisition unit as a function unit for acquiring a deviation amount between a mounting position of the LED element mounted by the LED element mounting unit and the predetermined mounting position, characterized in that the control device (100, 102, 104) also includes a first lens mounting unit as a function unit for mounting the lens on the board using a position of the LED element mounted on the board as a reference, when the deviation amount is smaller than a threshold value, and a second lens mounting unit as a function unit for mounting the lens in a preset position on the board, regardless of the position of the LED element mounted on the board, when the deviation amount is equal to or greater than the threshold value. a first lens mounting unit as a function unit for mounting the lens on the board using a position of the LED element mounted on the board as a reference, when the deviation amount is smaller than a threshold value, and a second lens mounting unit as a function unit for mounting the lens in a preset position on the board, regardless of the position of the LED element mounted on the board, when the deviation amount is equal to or greater than the threshold value.