It is probably fair to say that in the mind of the general public, occupational health is far more wary of physical chronic afflictions than mental and neurological sufferings. The best intuitive reason for investigating internal mental health is that it may assuage the unpleasant side of occupational health and lead to better job performance. Conformity to the well-documented studies, both physical and psychological factors should be equally treated. As an internal predictor of occupational health, psychological capital is a high-order construct extracted from organizational behavior. Interest in psychological capital(PsyCap) has expanded intensely in past decades. Strikingly, copious desired correlation outcomes have been obtained. It is widely substantiated in the empirical research that higher psychological capital is positively associated with results such as job innovation, working satisfaction, subjective well-being, and negative with stress, turnover, and burnout. Therefore, psychological capital is generally credited as a potent intervention in working settings to enhance occupational health. Multiple structural equation modelings(SEM) and self-report scales have been developed, have been validated for exploitation in various empirical scenarios, and are being employed in practical treatment. Yet, there has been scant heed to the antecedents in psychological capital. Although this has not preached as swiftly as consequences identification and prediction, or comparatively low, similar issues on gauging of antecedent variables likewise pertain vital to plumb the psychological capital. The reliable interventions towards psychological capital must be discovered and examined as well. Via sheer statistical association in the prior study, without more experimental causality proofs, previous conventional research approaches might be inadequate to fully explain the underlying principles of performance improvement through PsyCap. Against this, the analysis that follows this paper seeks to provide a more rounded elaborated review on the construction and causation of psychological capital from a causal inference perspective with the tenor to establish robust intervention.