Accurate detection of different structures in biological tissues is of great significance for clinical applications. In this study, a fully polarized Mueller matrix imaging detector for biological tissues is constructed to investigate the distribution of different representation vectors of the same sample or similar structures of different tissues on the Poincare sphere. In the current study, the spherical and column scatterers represented by nucleus and fiber are studied. The characterization effect of the P and D vectors at a high magnification is found to be better than that at a low magnification. In terms of the difference of the P and D vectors between the two tissues, the difference for the fibrous connective tissue is >8% than that of the skeletal muscle tissue. In general, the P vector is generally 19.7% better than the D vector for obtaining the difference between two structures in a single biological tissue. Internal biological tissue microstructure changes tend to be small and difficult to detect. The experiment conducted in this study confirms that the Poincare sphere can be used to distinguish different structures of biological tissues; the minimum surrounded by different scatterer balls can realize effective determination of biological tissue microstructure and has certain clinical application potential.