Retinoid molecules have possibilities for novel photonic devices. In this work, we deposited retinoid LB films, and measured absorption spectra of the films. The absorption maxima of the LB films of retinal mixed with DPPC red-shifted, when the area of the retinal molecules decreased. It would be due to the dipole interaction between retinal and DPPC. The absorption spectra of the LB films of retinoic acid had four peaks. It would be caused by the monomer and three type aggregates.