A semiconductor storage device includes: a plurality of first memory cells; a word line connected to gates of the first memory cells; a voltage generation circuit configured to generate voltage to be supplied to the word line on the basis of a set value; and a control unit configured to execute a write sequence that includes a plurality of loops, each loop including a program operation to increase a threshold voltage of at least part of the first memory cells to thereby write data to the first memory cells and a verify operation to verify the data written to the first memory cells. The voltage generation circuit generates voltage to be supplied to the word line at start of the verify operation on the basis of a first set value, and the control unit adjusts the first set value in accordance with progress of the write sequence.