To investigate how the use of photographs affects creativity, we have developed a system called GUNGEN-PHOTO, in which photographs are used to support idea generation. It consists of a collaborative workspace and personal workspaces and includes two main functions: photograph expansion for effectively extracting ideas from photographs, and outside comment addition for adding comments from personal workspaces. These functions are expected to increase the number of ideas generated. We conducted experiments on idea generation under the themes of “improvement” and “discovery, ” and found that more ideas were generated when photographs were used than when only text was used. We also found there were no significant differences in the quality of generated group between them.