|This paper presents learners´ perception of portfolio assessment. It discusses a possible relation between practice of language portfolio assessment and sustainability of motivation to learn second foreign language. More concretely, it addresses the question whether portfolio assessment helps learners to persist in learning second foreign language. After two decades during which portfolio assessment has been used on different education levels, there is no doubt about its usefulness and meaningfulness for both teachers and learners. In university courses of language for specific purposes, portfolio creates the possibility to include, among others, pieces of work related to learners´ personal disciplinary orientation and reflections of their intellectual needs to the language development evaluation. Documenting learners´ progress on language standards based on such pieces of work during the entire semester not only reinforces the sense of coherence and authenticity of learning but also permits the development of learners´ autonomy, which is so important for learners´ motivation. Moreover, this form of assessment manifests clearly a great variety of attributes that are necessary for sustaining motivation to learn a foreign language, such as possibility for learners to control their goals and progress, development of self-evaluation competencies, emphasis on effort, improvement of language skills, object of learning process, or teacher´s personalised approach to learners. The talk will present and discuss results of action research conducted during the Spring Semester 2018 in the French for Social Science course organised by the Masaryk University Language Centre (Brno, Czech Republic), and it will illustrate their integration into theoretical framework.