An operating method of a memory controller is provided. The operating method includes receiving a first read data and a second conversion information, the second conversion information including data obtained by converting a second read data based on a linear operation, and the first read data and the second read data including data read from same memory cells; converting the first read data based on the linear operation to generate a first conversion information; performing a logical operation on the first conversion information and the second conversion information to generate an operation information; performing an inverse operation of the linear operation on the operation information to generate a reliability information; and correcting an error of the first read data based on the first read data and the reliability information.