Outcome based education (OBE) helps to evaluate how well learning process achieves the outcome program and how far students achieved the intended learning outcomes. Problem based learning (PBL) approach is potential to assess the achievement of OBE. The aim of the present work is to describe how teaching and student assessment methods for implementing problem based learning (PBL) in Mass Transfer Operation course were adapted to the online learning during covid-19 pandemic. Based on the result of online class of Mass Transfer Operation course, the problem based learning method may be implemented well and interested to be developed. The students are motivated to experience the new collaborative learning way. The digital education will remain in place even when offline class is allowed.  Outcome based education (OBE) helps to evaluate how well learning process achieves the outcome program and how far students achieved the intended learning outcomes. Problem based learning (PBL) approach is potential to assess the achievement of OBE. The aim of the present work is to describe how teaching and student assessment methods for implementing problem based learning (PBL) in Mass Transfer Operation course were adapted to the online learning during covid-19 pandemic. Based on the result of online class of Mass Transfer Operation course, the problem based learning method may be implemented well and interested to be developed. The students are motivated to experience the new collaborative learning way. The digital education will remain in place even when offline class is allowed.