A non-volatile memory circuit includes a non-volatile memory having a first source and drain region having a non-LOCOS offset structure and a second source and drain region having a LOCOS offset structure. A pair of switch circuits are connected in parallel to the respective first and second source and drain regions for switching voltages applied to the first and second source and drain regions so that the first source and drain region serves as a drain and the second source and drain region serves as a source in a writing mode, the second source and drain region serves as a drain and the first source and drain region serves as a source in a reading mode, and equal voltages are applied to the first source and drain region and the second source and drain region in a retention mode.