The objective of this study is to investigate and construct a valid and reliable instrument to measure training effectiveness or the development of Training Effectiveness (TREF). The research was done through three TREF measures including satisfaction, learning performance, and behavioral change measures. The development of TREF was applied using descriptive statistics average variance explained (AVE), Composite Reliability (CR), and reliability. Data were analyzed using reliability analysis, and structural equation modeling (SEM) using confirmatory factor analysis (CFA) through Stata and Jamovi software. Significantly, the TREF developed in this study can be utilized as a tool to evaluate the efficiency of private and public sector training. As a result, this effort will support the development of high-quality human resources in the private and public sectors for efficient policy implementation, as well as the enhancement of training programs and employee work performance.