This study aims to illuminate what inference verification is and how such process is performed. To this end, this study looks at the concept of verification process during the inference process. Inference verification process is a process that readers present new reasons and grounds for an inference result or increases the validity of inference through counterargument and refutation. This process has differentiality, which is different from the checking and evaluating process in the existing inference process in that it is a process to persuade readers very actively for an inference result. This inference verification is based on critical thinking in that it verifies and evaluates validity for an inference result. Inference verification is a process thinking that moves in the better direction in that it continues to improve inference results with new reasons and grounds and that it reinterprets texts and presents new solutions to a problem and reveals the characteristics of critical thinking as creative reproductive process well. If inference verification is a positive persuasion process for an inference, it takes a form of argument. The type of inference verification depends on counterargument awareness. Inference verification without counterargument awareness takes not only a form that adds new reasons and grounds to inference result but also a form of ‘inference elaboration’ that presents the information related to the existing inference in more detail and of ‘inference expansion’ that makes the contents of inference much richer. Inference verification without counterargument awareness may increase the validity of inference by contradicting the counterargument recognized or modify or discard inference if you cannot contradict. Korean Language Education has emphasized the importance of inference, but few researches on the instructional methods designed for a valid inference have been performed. For readers to do a valid inference, further studies seem to be necessary because inference verification process is a process that requires a higher level of thought and educational contents related to this shall have to be provided with readers.