Dinoflagellate cyst (dinocyst) walls are composed of dinosporin, which most likely represents a suite of chemically different biopolymers that could be species specific. This is suggested by evidence of selective cyst degradation as well as studies from different dinoflagellate lineages, which report different macromolecular structures varying between aliphatic, carbohydrate-like, and predominantly aromatic. In order to investigate both the nature of dinosporin, the extent to which it may differ between dinoflagellate cyst taxa, and structural changes through time, we analyzed numerous species of dinocysts with micro-Fourier transform infrared (FTIR) analysis. Both Recent and Cretaceous age dinocysts were used. Initial results demonstrate that the chemical diversity of components making up dinocysts is great. It is quite probable that the Cretaceous-aged dinocyst spectra also incorporate post-depositional alteration of the original cyst wall, which complicates the interpretation of the original dinosporin structure. However, attempts to group different dinosporins on the basis of structural features are ongoing. Very preliminary results indicate it may be possible to distinguish some ecological features from the FTIR spectra of the Recent dinocysts.