The invention discloses a deployment constraint automatic detection method for Web application which comprises the following steps of: (1) establishing a deployment scheme model of the Web application of D(omega)=(U, R), wherein omega is the Web application, U is the entity set of the deployment scheme and R is the relation set among the entities; and (2) detecting the deployment constraint of the application according to the deployment scheme model. The invention can ensure that the method can automatically detect the deployment constraint of various types and in various planes after finishing the design of the deployment scheme model of the Web application; the method can automatically position and prompts users to modify the deployment scheme of the Web application to guarantee the satisfaction of the deployment constraint after detecting the current Web application to violate the deployment constraint; the success for carrying out the deployment operation according to the deployment scheme can be ensured; and the deployment efficiency and the accuracy of the Web application can be greatly enhanced.