A data protecting method, a memory control circuit unit and a memory storage apparatus are provided. The method includes generating a first temporary parity code group based on first data written into a first super physical unit; generating a second temporary parity code group by performing a logic operation on second data written into a second super physical unit and the first temporary parity code group; and generating an updated parity code group by performing the logic operation on the second temporary parity code group and the first data when data of the first super physical unit all become invalid data.