Research Paper Writing (RPW) plays a key role in completing all research work. Poor writing could lead to the postponement of publications. Therefore, it is necessary to develop a program of (RPW) to improve RPW ability for EFL/ESL writers, especially for undergraduate students in Higher Education (HE) institutions, which has caught less attention of curriculum developers so far. Therefore, this study aims to determine the core components of (RPW) program perceived as essential for EFL/ESL undergraduate students using Process Genre Approach (PGA) to develop a program of RPW. The Delphi Technique (DT) was used to validate those components through the interviews of experts including two boards of ten experienced and qualified lecturers of TESOL and curriculum studies in Can Tho University (CTU) in Vietnam and Universiti Sains Malaysia (USM). The results revealed that the core components of RPW program for EFL/ESL undergraduate students were determined and confirmed. This paper is therefore believed to make a great contribution to practical applications for RPW program developers, lecturers, undergraduate and postgraduate students in EFL/ESL contexts.