This study investigated the clothing easiness of movement when wearing casual Hanbok(Saenghwal Hanbok), as a high school student uniform, and produced some recommendations for improving the Hanbok. Casual summer-uniform Hanbok produced from different types of materials were produced for this study. They were P/R, P100, P/C, and P/R/S for the blouses, with P/W, P100, P/R, and P/W/F for the skirts. Their clothing easiness of movement were then tested at $25{pm}1^{circ}C$ and $50{pm}10%$ R. H. The results were as follows: The easiness of movement for casual Hanbok was marked as $3.7l({pm}1.03)$ on average which is higher than those of other garments, so it can be presumed that the easiness of movement for the tested clothes was quite good. The easiness of movement was lower, however, when students had their arms up front, right arms upright, arms crossed on the cheats, and bent forward whereas they were more comfortable when standing straight and sitting on a chair at 90 degrees. In terms of easiness of movement, the following ranking was revealed: waist, bust, shoulder, back, armhole, and upper arm. The easiness of movement for casual Hanbok skirts was quite good, and on average marked around $4.26({pm}.77)$. Standing straight was the most comfortable position, when they bend forward 45 degree and 90 degree were the most uncomfortable positions. The buttocks area was also more comfortable than the waist area for casual Hanbok skirts.