Abstract: Colour is considered as the basic visual perception of any space. There are numerous developed theories and assumptions related to the aesthetic comfort offered by colours, and to their effect on human psyche. In this paper, it is inspected how the choice of colour changes with age and its impact on that age group of people. This investigation will focus all the factors those are predicted to be more influential in architecture, interior spaces and the psychological status of users. The research aim of this study is to increase the concern about the importance of the interaction between interior space and human behaviour responding to the colour of the interior space. Paper talks about the importance of colour in an interior space where the different user groups spend most of their time like- schools for kids, offices for adults and meditation centre, old age homes for senior citizens. This research would help others to understand the importance of colour in the interior space and how people of different age groups respond to it. Based on the analysis of the conducted surveys and interviews, conclusions are drawn about the effect colours have on human behaviour in an interior space.