The low recovery of fine molybdenite is a major issue in mineral processing. In this study, fine molybdenite was used to investigate the effect of particle oxidation, sonication, edge to face ratio, and solution pH on its zeta-potential, self-aggregation, particle size distribution in pulp and finally flotation recovery. The experimental results show that fine, unoxidized molybdenite forms large aggregates when conditions and floats alone without collector, due to hydrophobic attraction between faces, which results in high recovery. Increasing pH reduces flotation recovery due to disaggregation resulting from the greater impact of edge surface charge. Oxidation (extreme) of molybdenite decreases its floatability dramatically across the pH range because of increased edge charge. Non-floating molybdenite is finer, oxidized and less aggregated material.