The application provides a memory device and an operation method thereof. The memory device includes: a memory array, for processing model computation having a plurality of input values and a plurality of interact coefficients; and at least one calculation unit. In receiving the input values, a first part and a second part of the memory cells generate a first part and a second part of the common source currents, respectively. The first part of the memory cells is electrically isolated from the second part of the memory cells based on a diagonal of the memory array. The at least one calculation unit calculates a first part and a second part of a local field energy of the model computation based on the first part and the second part of the common source currents.