Assessing student knowledge and success during and after teaching and learning is an embedded part of education since it offers important specifics for teachers. This action research was undertaken to inquire about students' and teachers' attitudes to portfolio assessment in their English courses. Two methods were employed, including a student portfolio attitude survey and a teacher survey. It was found that most students had a clear understanding regarding how a portfolio was made and admitted that the portfolio could assist them in learning how to write better in many aspects. Likewise, most teachers found the portfolio to be practical mainly in indicating students' problems and monitoring their learning progress. Implications from the study point to the need for training students to have skills important for using a portfolio as a life-long learning tool and for encouraging language teachers to use various forms of assessment to help students engage more in learning and ensure that targeted learning outcomes are achieved.