This paper intended to explore the problem solving behavior (PSB) of people in design tasks through simulated design process for interior works using interactive genetic algorithm (IGA). Through analysis of people's problem solving process when evaluating the juxtaposed images, it was revealed that people tend to do what they are certain of firstly, and make harder decisions later. The strategy helps them to unfold the problem gradually. It was also found that people did not tend to move their eyes to a faraway image in the interface constantly, which is more convenient for them.
