The invention discloses an analysis and computation method for the structural strength of an elevating drilling platform, comprising the following steps: building a finite element model according to the structure point of a drilling platform; determining an environment condition according to the operational sea area of the drilling platform; determining a variable load; combining different environmental working conditions with the variable load to obtain different computation working conditions; analyzing and calculating each computation work condition; after each computation working condition is calculated, checking the computation result from seven aspects according to relevant standards; drawing the environmental map of the drilling platform by taking the environment condition and the maximum lifting capacity as parameters; and inquiring the map to obtain the true state of the drilling platform under the practical use condition. The method has the outstanding characteristics of more computation working conditions, more manpower and time are consumed if people manually operate to finish the computation, but the dedicated program software which is compiled by the method and is dedicated for the environmental map can finish all computations within short time. Meanwhile, the software supports parallel computation so as to further shorten computation time.