The invention discloses an intelligent control method and an intelligent control system for an offshore petroleum platform power grid, and relates to a method and a system for monitoring an offshore oilfield group power grid. The method comprises that a wide-range intelligent monitoring system and a multi-target coordinated optimization operating system are arranged; the multi-target coordinated optimization operating system carries out restricted non-linear optimization on corresponding targets on the basis of synchronous data collected by the wide-range intelligent monitoring system; and an intelligent self-healing control system carries out control strategy decision making according to optimization results and automatic control on relay protection, switches, automatic safety devices and automatic adjusting devices. The system disclosed by the invention comprises the wide-range intelligent monitoring system, a dynamic early warning system, the multi-target coordinated optimization operating system and the intelligent self-healing control system. The intelligent control method and the intelligent control device solve a problem that the safety and the economy of the power grid cannot be precisely monitored and evaluated because of incomplete information, varied operating modes and uncertainty of model parameters, and problems of coupling of multiple control targets and coordination of multiple control measures of the offshore oilfield group power grid in a complex operating environment, thereby realizing comprehensive regulation of reactive power and active power of the power grid, and achieving an objective of automatic optimization operation.