This study investigated the seat layout of automobile interiors and its impact on the fluidity and privacy of interior space using spatial perception and space syntax research methods. The interior of an automobile is a typical “miniature” passenger space. First, to explore the perception characteristics of interior space fluidity and privacy across different seat configurations, we conducted a perception experiment on the interior space of seven automobile models with various seat layouts. The depth, connection, global integration degree, and standardized integration degree values were obtained using spatial syntax to perform topological calculations on the experimental automobile models. We conducted a correlation analysis in conjunction with the results of the perception experiment and the spatial syntax analysis. The calculation results of spatial syntax analysis are consistent with the experimental results of perception of automobile interior space layout on the fluidity and privacy. The different layout of automobile seats can affect people's perception on the fluidity and privacy of automobile interior space. At the same time, spatial syntax can provide an effective design analysis tool for the fluidity and privacy of automobile interior space.