A nonvolatile memory device for reducing programming current and improving reliability comprises a memory cell array, a write circuit, and a verification circuit. The memory cell array comprises memory cells arranged at crossing points of a bit-line and word-line matrix of the memory cell array. The write circuit provides multiple variable pulses to each word-line for programming. The multiple variable pulses have predetermined amplitude for keeping gate injection current roughly maximum while lowering conduction current during programming operation. The verification circuit senses variation of the conduction current during the programming operation, and disables the programming operation if the sensed conduction current during the programming operation reaches a predetermined value.