The development of functional nano-crystalline cellulose hybrid suspensions has been in the focus of many areas of industry and academia for the past decades. The attention is elucidated from a unique biocompatible, mechanical, solution etc. properties of cellulose based systems. Fabrication of functional cellulose hybrids with customized features requires detailed knowledge of their final properties as well as understanding the structure–property relationships between the initial ingredients. The reported study investigates the formation and corresponding fundamental solution and molecular characteristics of highly disperse nano-crystalline cellulose hybrids with aluminum oxide nanoparticles. The characterization of the final complexes and its primary components was performed mainly in solution, using basic complementary hydrodynamic approaches, substantially—sedimentation velocity analysis in the analytical ultracentrifuge and related techniques. The analysis of the solution behavior resolved information about the hydrodynamic size, molar mass, shape, asymmetry and composition of the complexes. Additionally morphology of the cellulose hybrids was investigated by scanning force microscopy. To this end we demonstrate complete structural examination of highly disperse colloidal suspensions of crystal nano-cellulose modified by aluminum nanoparticles using classical solution characterization techniques. Graphic abstract: [Figure not available: see fulltext.]