A convex relaxation evaluation method for maximum absorbing capacity of wind power, The invention firstly obtains statistical characteristics such as mean value, variance and probability density function by analyzing historical data of wind power output, and then establishes opportunity constrained capacity evaluation model for power system, in which risk constraints of cross-sectional power flowexceeding limit and risk constraints of rotating reserve shortage are taken into account. Then the opportunity constraint is relaxed into a deterministic convex constraint, and the original problem istransformed into a convex optimization problem which is easy to solve. Finally, the scheduling model is solved to obtain the maximum absorbable capacity. The invention fully considers the advantagesof stochastic dynamic optimization of wind power absorbing capacity evaluation, Considering the security and economy of decision-making process, the opportunity constraint problem which is difficult to be solved is relaxed into a convex optimization problem which is easy to be solved by the convex relaxation method, which improves the efficiency and flexibility of the system operation and effectively reduces the risk of the system.