Production line for mounting electronic components

There is provided a production line having a plurality of mounting apparatus of electronic components in which the overall production efficiency is sustained by an alternation scheme when a mounting apparatus has a long cycle time due to a high malfunction rate. At a predetermined timing, the rate of unsuccessful pick-up procedure for an electronic component is compared to a predetermined value. If the rate is higher than the value, CPU finds out if the mounting apparatus 2, or 3 is available as an alternate. When the alternate is the apparatus 2, CPU 10 changes the command parameter of the particular mounting procedure, stored in RAM 12, from "M" to "S", and stops mounting the same component. In the mean time, the mounting apparatus 2 accepts the alternate request from the apparatus 1, changes the command parameter as required, and mounts the same component on a print circuit board.