Disclosed is a data compression method for DeMura table, including steps of: acquiring an original DeMura table of a display panel; designating compensation data in four neighboring rows in the original DeMura table as a fragment to be fetched in a fetch cycle and periodically fetching compensation data per fetch cycle; permuting fetched compensation data so as to create a compressed DeMura table; and storing the compressed DeMura table in a storage device, wherein the step of periodically fetching compensation data includes sub-steps of: fetching the compensation data in odd-numbered columns from the first row of the original DeMura table; and fetching the compensation data in even-numbered columns from the third row and fetching the compensation data in the first column from the third row of the original DeMura table. Also disclosed is a data decompression method for DeMura table. The invention can save storage space and lower cost.