A solder printing system, comprising: an upstream printer and a downstream printer each including: (a) a first conveyor lane and a second conveyor lane which are disposed side by side in an intersecting direction that intersects a substrate conveyance direction and each of which is configured to convey a circuit substrate in the substrate conveyance direction; and (b) a solder printing device configured to print solder cream on the circuit substrate conveyed by the first conveyor lane; and a conveyor-lane changer disposed between the upstream printer and the downstream printer for inputting the circuit substrate conveyed by the first conveyor lane of the upstream printer into the second conveyor lane of the downstream printer and inputting the circuit substrate conveyed by the second conveyor lane of the upstream printer into the first conveyor lane of the downstream printer, wherein each of the upstream printer and the downstream printer has a controller (82a, 82b) for controlling a corresponding one of the upstream printer and the downstream printer, the controller (82a, 82b) of one of the upstream printer and the downstream printer being configured to control also the conveyor-lane changer, characterized in that the solder printing system further comprises an information storage device (148, 150) to store performed printing information for each of the circuit substrates output from the solder printing system, in association with an order in which the circuit substrates are output, the performed printing information including printing-apparatus identification information that is information for identifying which one of the solder printing device of the upstream printer and the solder printing device of the downstream printer has printed the solder cream on said each of the circuit substrates output from the solder printing system. an upstream printer and a downstream printer each including: (a) a first conveyor lane and a second conveyor lane which are disposed side by side in an intersecting direction that intersects a substrate conveyance direction and each of which is configured to convey a circuit substrate in the substrate conveyance direction; and (b) a solder printing device configured to print solder cream on the circuit substrate conveyed by the first conveyor lane; and a conveyor-lane changer disposed between the upstream printer and the downstream printer for inputting the circuit substrate conveyed by the first conveyor lane of the upstream printer into the second conveyor lane of the downstream printer and inputting the circuit substrate conveyed by the second conveyor lane of the upstream printer into the first conveyor lane of the downstream printer, wherein each of the upstream printer and the downstream printer has a controller (82a, 82b) for controlling a corresponding one of the upstream printer and the downstream printer, the controller (82a, 82b) of one of the upstream printer and the downstream printer being configured to control also the conveyor-lane changer, characterized in that the solder printing system further comprises an information storage device (148, 150) to store performed printing information for each of the circuit substrates output from the solder printing system, in association with an order in which the circuit substrates are output, the performed printing information including printing-apparatus identification information that is information for identifying which one of the solder printing device of the upstream printer and the solder printing device of the downstream printer has printed the solder cream on said each of the circuit substrates output from the solder printing system.