The beneficiation efficiency of andalusite ores is strongly governed by particle size because of its effect on mineral liberation and separation selectivity. In this study, the effect of particle size on the upgrading performance of an andalusite ore from the Moroccan Sidi Bou-Othmane deposit was investigated using shaking table gravity concentration followed by dry high-intensity magnetic separation. Optical microscopy revealed a progressive increase in mineral liberation, from 61% in the 600–900 µm fraction to 92% in the 45–150 µm fraction. Although the finest fraction produced the highest Al2O3 grade (41.35 wt.%), metallurgical recovery remained limited (21.90%) owing to excessive entrainment of ultrafine particles during gravity separation. The 150–355 µm fraction provided the optimum balance between concentrate grade and recovery, yielding a gravity concentrate assaying 38.03 wt.% Al₂O₃ with a recovery of 78.30%. X-ray diffraction analysis confirmed significant enrichment of andalusite in the concentrate, accompanied by preferential rejection of quartz-rich gangue minerals. Subsequent dry high-intensity magnetic separation further improved concentrate quality by decreasing Fe₂O₃ content from 5.80 to 1.79 wt.% while slightly increasing Al₂O₃ content to 38.72 wt.%. SEM observations revealed angular, largely liberated andalusite grains with limited residual gangue attachment, consistent with the mineral liberation determined by optical microscopy. The reduction in Fe₂O₃ content was confirmed by XRF analysis. These findings provide quantitative insights into liberation-controlled andalusite beneficiation and establish, at laboratory scale, a low-cost pre-concentration route for low-grade andalusite ores. The shaking table stage showed statistically significant differences among the investigated particle-size fractions, while replicate trials assessed experimental reproducibility.