In order to evaluate the economy of openhole cementing sidetracking in the same layer and openhole sidetracking in casing to optimize the way of sidetracking, the conventional design and operation processes of 2 wells by the same layer sidetracking are introduced. The period of screen pipe fishing in well abandonment and the economy of openhole cementing sidetracking are analyzed, by establishing a decision graph of sidetracking scheme, the key factors affecting the economy of sidetracking are seeked out, and the calculation method concluded for the economic construction period of screen pipe fishing and critical surplus construction period of the economy can be used as the decision basis for whether the screen pipe fishing scheme should be adjusted or not.