Abstract The relationship between working memory and long-term memory was one of the main problems in recent studies of working memory. As part of this problem, we examined the neural substrates that sustain the semantic coding process in verbal working memory using fMRI. In past experiments, we behaviorally explored whether central executive plays an important role in the process of semantic coding; thus, we especially focused on the function of anterior cingulate cortex (ACC) that is assumed to form the main neural basis of central executive. We accomplished our purpose by examining the concreteness effect reflecting semantic information. The ACC was strongly activated under the Concrete condition in contrast to the Abstract condition. Based on this result, we argue that the ACC is responsible for the semantic coding process in verbal working memory.