This article aims to explore contemplative practitioners’ direct lived experiences of enlightenment and develop a multi-item scale measuring these experiences. A mixed-method approach was adopted. The first study is a phenomenological study that interviewed 24 participants with enlightenment experiences and the second study is a scale-development study that recruited 1130 participants for scale validation. Two major clusters of the enlightenment experiences including sensory feelings and nondual realizations emerged from the phenomenological study and the four main themes of the realizations were (...) formed: intrapersonal insights, inspiration internalization, interpersonal compassion, and interconnectedness. After exploratory factor analysis and confirmatory factor analysis, a three-factor structure of the Spiritual Enlightenment Experience Scale, including nonduality, sensory clarity, and sensory disappearance were revealed. The findings of the research depicted a fuller picture of spiritual enlightenment experiences which may contribute to the current knowledge of religiosity and spirituality, as well as transpersonal psychology. The results suggest that the core components of spiritual enlightenment experiences include sensory clarity and disappearance experiences and realizations of nonduality. (shrink)