The invention discloses a reliability evaluation method and system for a wind electricity-photo-electricity-stored energy-containing power generation and transmission system. The method comprises thefollowing steps that: an element reliability model is constructed based on resource and load fluctuation characteristics; fault states of elements and corresponding fault rates are obtained accordingto the reliability model; the fault states are sampled, so that a fault state set can be formed, and fault rates corresponding to the fault states in the set are acquired; operation simulation is performed on the wind electricity-photo-electricity-stored energy-containing power generation and transmission system based on the reliability model, so that power generation and load power balance can berealized; the power flow of the wind electricity-photo-electricity-stored energy-containing power generation and transmission system is calculated; generator tripping and load shedding are carried out according to the calculation result of the power flow of the wind electricity-photo-electricity-stored energy-containing power generation and transmission system; and the reliability indexes of thewind electricity-photo-electricity-stored energy-containing power generation and transmission system are calculated and put into statistics, and reliability evaluation is performed on the wind electricity-photo-electricity-stored energy-containing power generation and transmission system according to the reliability indexes. With the method and system of the invention adopted, annual operation simulation is carried out on the resource-network-load-storage system, so that the accuracy of the reliability evaluation is improved.