A work system for substrates, comprising: a plurality of working machines (12, 14, 16, 18, 20) that are arranged in a line and that each includes a pair of substrate conveyance devices (22, 24; 76, 78; 88, 90) for conveying circuit substrates through two paths; and a control device (102, 104, 106, 108, 110) configured to control operations of the pair of substrate conveyance devices (22, 24; 76, 78; 88, 90) of each of the plurality of working machines (12, 14, 16, 18, 20), the work system for substrates being configured such that the circuit substrates are conveyed through the two paths from a working machine disposed upstream out of the plurality of working machines (12, 14, 16, 18, 20) to a working machine disposed downstream, wherein the control device (102, 104, 106, 108, 110) includes a substrate conveyance control unit (130, 132) configured to control the operations of the pair of substrate conveyance devices (22, 24) of the upstream working machine and of the pair of substrate conveyance devices (88, 90) of the downstream working machine, characterized in that the substrate conveyance control unit (130, 132) is configured to control the operations of the pair of substrate conveyance devices (22, 24) of the upstream working machine and the pair of substrate conveyance devices (88, 90) of the downstream working machine such that, in a state in which a circuit substrate of which the work result is good and a circuit substrate of which the work result is not good are able to be conveyed to the downstream working machine by the pair of substrate conveyance devices (22, 24) of the upstream working machine, the circuit substrate of which the work result is not good is conveyed to the downstream working machine earlier than the circuit substrate of which the work result is good. a plurality of working machines (12, 14, 16, 18, 20) that are arranged in a line and that each includes a pair of substrate conveyance devices (22, 24; 76, 78; 88, 90) for conveying circuit substrates through two paths; and a control device (102, 104, 106, 108, 110) configured to control operations of the pair of substrate conveyance devices (22, 24; 76, 78; 88, 90) of each of the plurality of working machines (12, 14, 16, 18, 20), the work system for substrates being configured such that the circuit substrates are conveyed through the two paths from a working machine disposed upstream out of the plurality of working machines (12, 14, 16, 18, 20) to a working machine disposed downstream, wherein the control device (102, 104, 106, 108, 110) includes a substrate conveyance control unit (130, 132) configured to control the operations of the pair of substrate conveyance devices (22, 24) of the upstream working machine and of the pair of substrate conveyance devices (88, 90) of the downstream working machine, characterized in that the substrate conveyance control unit (130, 132) is configured to control the operations of the pair of substrate conveyance devices (22, 24) of the upstream working machine and the pair of substrate conveyance devices (88, 90) of the downstream working machine such that, in a state in which a circuit substrate of which the work result is good and a circuit substrate of which the work result is not good are able to be conveyed to the downstream working machine by the pair of substrate conveyance devices (22, 24) of the upstream working machine, the circuit substrate of which the work result is not good is conveyed to the downstream working machine earlier than the circuit substrate of which the work result is good.