A memory device for CIM, applicable to a 3D AND-type flash memory, includes a memory array, input word line pairs, and a signal processing circuit. The memory array includes first and second pairs of memory cells. Each first pair of memory cells includes a first memory cell set coupled to a first GBL and a second memory cell set coupled to a second GBL. Each second pair of memory cells includes a third memory cell set coupled to the first GBL and a fourth memory cell set coupled to the second GBL. Each input word line pair includes a first input word line coupled to the first and the second memory cell sets, and a second input word line coupled to the third and the fourth memory cell sets s. The signal processing circuit is coupled to the first and second global bit lines.