Although regularity refers to the compatibility between pronunciation of character and sound of phonetic component, it has been suggested as being part of consistency, which is defined by neighborhood characteristics. Two experiments demonstrate how regularity effect is amplified or reduced by neighborhood characteristics and reveals the regularity effect without the confounding of neighboring characters. Experiment 1 examined the regularity effects of characters with more than one neighboring character, the results of which indicated that the consistency of irregular characters decides the patterns of regularity effects. Experiment 2 included characters without neighboring characters and measured the interaction of character frequency and regularity effect. The interactions of the characters with neighboring characters were reduced by the neighborhood characteristics of irregular characters, but a marginal interaction was found for characters without neighboring characters. The theoretical implication that regularity is acquired from lexical knowledge of phonetic components rather than accumulated from neighboring characters is discussed.