The present invention provides a nonvolatile semiconductor memory device that can optimize a timing of performing an error detection and correction process to shorten a processing time. Upon receiving a write request to a memory cell array including a variable resistive element where information is stored based on a resistance state of a variable resistor, an input/output buffer outputs write data to a write control unit and an ECC control unit. The write control unit performs a data write process of writing divided data, obtained by dividing the write data into a predetermined number of data, to the databanks. The ECC control unit generates a first error correction code by performing an error correction code generation process to the write data or the divided data, in parallel with the data write process. The write control unit performs a code write process of writing first test data into an ECC bank.