The present disclosure relates to a system for predicting abnormality occurrence using a PLC log data, the system including a controller configured to receive a data from a lower-level device connected to a PLC data log module and determine the data, and to store the data in an event storage when the data is a data related to abnormality occurrence, an analyzer configured to generate an abnormality analysis result by analyzing the data related to abnormality occurrence, and an analysis result storage configured to store the abnormality analysis result, wherein the controller compares the data transmitted from the lower-level device with the abnormality analysis result stored in the analysis result storage, and generates an abnormality occurrence prediction signal, when it is determined that the data transmitted from the lower-level device is similar to the abnormality analysis result.