Abstract: This study investigates near-field distance discrimination of virtual sound sources under bone conduction (BC) reproduction at the mastoid and compares it with air conduction (AC). Near-field virtual sounds are synthesized using far-field non-individualized head-related transfer functions (HRTFs) combined with distance variation functions. Two types of stimuli are used: one preserving natural intensity variation with distance, and the other with normalized amplitude. Distance discrimination thresholds are measured under different directions (lateral, rear), stimulus orders (approaching, receding), and reference distances (0.5 m, 1.0 m). Results show that intensity serves as the primary cue for distance perception in both AC and BC conditions, and no significant differences are found between reproduction modes when intensity cues are present. With amplitude normalization, no significant difference is observed between AC and BC in rear-direction stimuli, whereas BC leads to significantly higher thresholds than AC in lateral-direction stimuli, possibly due to crosstalk interfering with binaural cues. Additionally, thresholds under BC are lower in the approaching order than in the receding order, suggesting that BC reproduction also preserves preparatory responses to approaching sound sources.