The invention discloses an online operation management system for a coalmine high-voltage power network employing multi-mode setting calculation. The system comprises an intelligent terminal, an engineer station, communication substations and integrated protection devices of high-voltage switches, wherein the intelligent terminal achieves a setting calculation function on a power supply system under various operation modes according to the power supply relationship between electric equipment of a coalmine high-voltage power supply system and closing and opening states of the high-voltage switches, and can manage generated constant value schemes under various operation modes on the basis of a constant-value identification switch; meanwhile, the engineer station of the system can arrange multiple constant value schemes into the integrated protection devices of the high-voltage switches through the communication substations; when the operation state of the power supply system changes, the intelligent terminal of the system can timely send out an alarm, reminds the engineer station to carry out scheme switching, does not need to reset a constant value of each integrated protection device when the operation mode changes, and can relatively quickly finish switching of the constant-value schemes.