The niobium (Nb)-rich mineralization bed in the Late Permian strata of southwestern China, which is mainly composed of clay rocks with different titanium contents, has attracted much attention. Previous studies have suggested that Nb is associated with TiO₂ minerals. It is also supposed that there should be other Nb-bearing minerals in addition to TiO₂ minerals, especially for Nb-rich samples with low-TiO₂ contents. So far, the Nb distribution in low-TiO₂ content clay rocks has not been understood. In this study, the dominant Nb-bearing minerals in low-TiO₂ (L-Ti-Clay) and high-TiO₂ (H-Ti-Clay) kaolinitic clay rocks were investigated and compared using SEM (scanning electron microscopy), TEM (transmission electron microscopy), and EPMA (electron probe micro-analysis) analyses. The results showed that ilmenite, anatase, and zircon are the host Nb-bearing minerals of the L-Ti-Clay sample. The average Nb₂O₅ content descended in the following order: anatase (5.08 wt% Nb₂O₅), zircon (0.92 wt% Nb₂O₅), and ilmenite (0.78 wt% Nb₂O₅). For the H-Ti-Clay sample, the host Nb-bearing minerals are anatase and ilmenite, with an average Nb₂O₅ content of 0.56 and 0.33 wt%, respectively. All the anatase and ilmenite particles and approximately 52 % of zircon particles in the L-Ti-Clay sample contain Nb, while in the H-Ti-Clay sample, approximately 75 % of the anatase and 30 % of the ilmenite particles are Nb-containing. Overall, anatase is the biggest contributor of Nb for both L-Ti-Clay and H-Ti-Clay samples, with a Nb-bearing proportion of 50.91 and 48.05 wt%, respectively. The findings of this work interpret the reason that low-TiO₂ clay rock contains high Nb and are also instructive for Nb and Ti resources utilization.