This study aims to understand the foreign language learner’s internal process while they are translating. To figure out invisible internal process of the learner, Key logging during translation process, short interview after translating and behavioral observation were used. For considering behavioral characteristics for internal process, Pause, Deletion, Moving and Mistranslation were chosen. In particular, Pause was chosen to work as criterion when analyzing other behaviors. By analyzing those behaviors, three internal processes were found: (1)Deliberatiing on words or phrases following the pauses, (2)Considering ill-matched words or phrases between source text and target text, (3)Continuous checks on what writers had written down. Deliberations were generally found before the long-term pause. Learners were deliberating what to write on next phrases, due to their scarce knowledge of grammatical collocation of the target language. Considering ill-matched words or phrases between source text and target text shows variety of behaviors such as moving, deletion after the long-term pauses. According to the learners’ interview and researcher’s observation, it was arisen when the learners are fail to find the acceptable expressions in target language. Continuous checks on what learners had written down were generally found after the translation was finished. Entire part of target text was examined in this type of process. Thus, long period of pause was required for reading source text and target text, also deletion and moving was required for correcting mistranslated words or phrases. It infers that learners’ behaviors are combined to suggest certain meanings of internal process. Thus, these behaviors do not suggest solid internal process. With more elaborated analysis, this