This research was to explore how people react to different composition of landscape images and what kinds of landscape composition patterns were preferred. Applying the principle of western painting to classify the landscape composition patterns, the study generalized five kinds of compositions, including horizontal, vertical, triangular, oblique, and zigzag compositions. This research also probed the relationships between the patterns of landscape composition and physiological, psychological, and preference reaction of subject's examinees viewing the landscape photos. There were 20 landscape photos, which included four photos for each type of composition and were tested on 40 participants. Eye-tracking system was utilized to measure the physiological reactions (pupil aperture size, and visual locus length) of the subjects, and a questionnaire was used to survey subject's, psychological reactions (coherence, legibility, complexity, and mystery) and preference value. The study obtained three major findings. (1) For physiological reaction, there were on significante difference in the length of visual locus, but there were significant differences in pupil aperture. (2) The subjects had different psychological reactions when viewing different composition of Ahotos. Horizontal and traingular composition patterns had higher scores in coherence, oblique and horizontal composition patterns had higher scores in legibility, zigzag and triangular composition patterns had higher scores in complexity, while vertical, oblique and zigzag composition patterns had higher scores in mystery. (3) The subjects showed significant preference scores when looking at the photos with different kinds of composition pattern. Triangular and horizontal composition patterns were more preferred than the other patterns in this research. Vertical composition pattern had the least preference value. Discussion and suggestion for further research were also included.