Portfolio assessment is a learner-centered assessment and it is also an assessment for learning. A study with a class of 31 first-year English education majors in 2011-2012 was conducted. The development and implementation of portfolio assessment in the integrated English course was described, and then a survey on the learner's perception toward the use of the portfolio assessment was conducted. The results showed that student have positive attitude toward the use of the portfolio assessment, the portfolio assessment developed students' language competence, enhanced their cross-cultural knowledge and promoted their learning autonomy and motivation. Finally the problems in using the portfolio were discussed.