This study surveyed the expression areas of the Synthetic House-Tree-Person drawing test (S-HTP test, Mikami, 1995) for Japanese early adolescents. The S-HTP test is a projective method in which subjects are asked to draw a house, tree, and person. The expression area is defined as the area of each drawn item, such as the house, tree or person. The participants consisted of 186 Japanese junior high school students and their S-HTP drawings were analyzed using path analysis. The relationships between the expression areas of each item in the test and the students' personality traits were examined. The personality traits were measured using the Five-Factor Personality Inventory for Children (FFPC, Soga, 1999). The results show that personality traits of high conscientiousness were associated with larger houses (p < .10) and trees (p < .10). In addition, higher scores on openness to experience (p < .01) and on agreeableness (p < .05) correlate with bigger person figures as their size, whereas higher scores on neuroticism correlate with smaller figures as their size (p < .01). The findings also indicate that the total fitness of the model was sufficient (CFI = .984, RMSEA = .021). These findings may aid the development of useful criteria for future psychological assessments.