Humanistic psychologists emphasize more of a positive, optimistic view of human nature which highlights an individuals inherent goodness and their potential for personal growth.
Existential psychologists focus more on the individual as a responsible agent who is free to create and live his or her life while negotiating the issue of meaning and the reality of death
References:
Gilbert, Daniel T., Daniel M. Wegner, and Matthew K. Nock. "Personality."Psychology. By Daniel L. Schacter. Third ed. N.p.: Worth, n.d. 471-503. Print.
Gilbert, Daniel T., Daniel M. Wegner, and Matthew K. Nock. "Personality."Psychology. By Daniel L. Schacter. Third ed. N.p.: Worth, n.d. 471-503. Print.