This paper aims to puzzle out factors contributing to the proposed set of hypothesized relationships inducing perceived electronic worth-of-mouth (eWOM) credibility and purchase intention of Vietnamese Millennials when seeking for hotel reviews on Online Travel Agencies’ (OTAs) site. The study uses a quantitative approach throughout surveying 365 correspondents in social network sites from February to April of 2018. The findings illustrated that booking intention of Vietnamese Millennials was affected mostly by source trustworthiness. Some notable peculiarities in research findings due to the potential differences in nature of OTAs’ site have contributed to the debate of existing eWOM literature. Specifically, the current findings not only enrich understanding of factors inducing perceived eWOM credibility but also benefit marketers by providing preliminary recommendations in approaching Vietnamese Millennial eWOM receivers, also known as the most potential consumers, on OTAs’ platform via credible eWOM initiatives.