The invention discloses a method for participating in short-term generation plan arrangement and standby optimal configuration considering new energy access and demand side response, and belongs to the field of safety planning and operation of electric power systems. The method comprises the following steps of: obtaining basic data of an electric power system; establishing a constraint condition by using minimum system total cost as a target function; based on the thought of decomposition and coordination, decomposing the problem of solving an optimization model formed by the target function and the constraint condition into solving four sub-problems which comprise a first safety constraint unit commitment sub-problem, a primary standby adequacy check sub-problem, a secondary negative standby adequacy check sub-problem, and a secondary positive standby and tertiary standby adequacy check sub-problem; if the last three sub-problems all satisfy requirements by checking, the problem is solved; and if the last three sub-problems do not satisfy the requirements, modifying the unit and standby configuration, and entering the first safety constraint unit commitment sub-problem to carry out resolving until convergence is finally realized. The method disclosed by the invention can be used for effectively solving the large-scale multi-fault state random unit commitment problems.