Mueller matrixes are presented for optically inactive and fluorescent samples with and without photo-selection, and for optically active and fluorescent ones with and without photo-selection, in order to analyze phenomena observed in fluorescence polarization. Absorption-fluorescence transformation matrices are introduced in the derivation of formula to take account of the process occurring during the interval between excitation and emission. Mueller matrix expressions derived are used for investigating the problems of circularly polarized emission (CPE) and linearly polarized emission (LPE) measurements. It is found that they are useful not only in analyzing the effects of experimental systems on fluorescence polarization spectroscopy but also in the design, analysis, and evaluation of CPE and LPE spectrometers.