The primary objectives of this analysis are divided into two, first is to determine the relationship between PHEI's Characteristics which are academic programs, tuition fees, reputation, location, employment opportunities, external factors which are electronic word of mouth (EWOM) and word of mouth (WOM) as independent variables towards students' decision-making as the dependent variable to enrol at a private HEI in Malaysia. Secondly is to find out the significant factor influencing students' decision to register at private HEI.The Theory of Reason and Action (TRA) was the guiding theory used in this study for EWOM and WOM, and the Theory of Planned Behavior (TPB) was used for the characteristics of private HEI, such as academic programs, tuition fees, reputation, location, and employment opportunities. A quantitative and stratified sampling method were applied in this research. Four hundred and fifty (450) questionnaires were distributed on a recommended sample for undergraduate students from 6 selected private HEIs with university status in Kuala Lumpur and Selangor. IBM SPPS (version 23) was used to analyze the data to test the hypotheses. After deleting the outlier, only 409 cases were held for research in this research. The researcher's conclusions resulted in a significant influence of academic programs, tuition fees, reputation, location, employment opportunities, and EWOM towards students' decision-making to enrol in a private HEI. Thus, all hypotheses proposed are significant. This paper addresses an interesting issue related to the factors of Private HEIs' characteristics and marketing channel influence students' decision-making to enrol.