The present invention relates to a cyclodextrin derivative, a method for preparing the same, a photoresist composition, a color photoresist and a display device. The cyclodextrin derivative particularly is a α-cyclodextrin modified polymerizable monomer represented by the following formula I or I′, wherein k is any integer selected from 2-6, n is any integer selected from 1-3, R is an aromatic ring having 5 to 30 carbon atoms, R′ is a multivalent straight or branched carbon chain having 5 to 30 carbon atoms which may optionally be interrupted by O. The α-cyclodextrin modified polymerizable monomer can be applied to a photoresist composition which has small aberration and high transmittance, thereby improving the display quality of the display apparatus.