Individual differences play a crucial role in determining the extent to which second language (L2) acquisition can be effectively achieved. Despite the progress in linguistics research, investigations into individual differences within L2 phonetics remain relatively underexplored compared with other linguistics domains. This study endeavors to scrutinize the interplay between individual differences and L2 phonetics, focusing on three fundamental cognitive faculties: phonological short-term memory, attention, and inhibitory control. Through a systematic review, the study outlines research methodologies, findings, and contentious points in this area. Additionally, it provides insights into potential directions for future research in the field of L2 phonetics.