This reasearch aims to find-out: (1) the effect of mind habit by using portofolioassessment. (2) the effect of concept mastery through implementation of portofolio assessment.This research was conducted to science ninth graders of SMAN X Bandung on 2012/2013academic year. The sample of this research was 48 students. The data were collected for sevenmeetings by applying two concepts; ecretion and nervous systems. The instruments used in thisstudy ;Habit of Mind Questionnaires, Test of Secretion and Nervous System Concepts, andQuestionnaire of Students' views about learning process.The results of this research showed thatcategory of critical thinking and self regulation improved and stayed in middle level, meanwhilecreative thinking is on low level. Students' concept mastery of ecretion and nervous systemsimproved after portofolio assessment implemented. The Average of the improvement stayed inhigher standard 0,55 from 0,31. For over all, the students gave positive responds for the use ofportfolio assessment.