The present invention provides an IO point communication range detection method. The method comprises: the step S1, traversing an engineering device table, finding out all the control station devices in the engineering device table, reading subscript data corresponding to the control station devices from a subscript corresponding table, obtaining the communication ranges of IO points with different data types of the control station devices, storing the communication ranges of IO points into a control station information array; the step S2, traversing all the control stations in the control station information array; the step S3, finding an IO point capable of switching on a communication switch or a value writing switch in each control station, and obtaining the information of the IO point; and the step S4, comparing the information of the IO point with the communication ranges of the IO points with different data types of the reading control station device, and determining whether the IO point exceeds the communication range of the control station or not. The present invention further provides a plugin capable of executing the method mentioned above and a computer readable medium comprising the plugin. The IO point communication range detection method and plugin, and the computer readable medium can check all the communication IO points exceeding the range so as to ensure that all the IO points of the current engineering is located in the communication range of the actual control station.