Objective To investigate the differences in neural responses related to consciousness activity under loss of responsiveness (LOR) and loss of consciousness (LOC) states through auditory event‑related potential (AERP). Methods An auditory experiment based on the Oddball paradigm was used to explore the differences in the average wave amplitudes of AERP, including the mismatch negativity (MMN) and P300 components, in healthy subjects under the LOR and LOC states through propofol sedation. Results Twenty‑five healthy subjects were included for data analysis. The results showed that there was statistical difference in the average wave amplitudes of MMN induced by novelty (MMN‑Nov) between the LOR and LOC states [(−4.2±5.0) μV vs (−0.6±6.4) μV, P<0.05]. However, no statistical difference was found in the average wave amplitudes of P300 induced by deviation (P300‑Dev) and P300 induced by novelty (P300‑Nov) between the LOR and LOC states [P300‑Dev: (1.5±3.0) μV vs (1.9±4.3) μV, P>0.05; P300‑Nov: (2.3±4.6) μV vs (2.1±5.3) μV, P>0.05]. Conclusions The MMN‑Nov shows a difference between propofol‑induced LOR and LOC states, which may serve as an electrophysiological indicator for differentiating LOR and LOC under the effect of anesthetic sedation.