The present paper is devoted to discuss and analyze the simulation of the pollutant transmission characteristics in anoffice room with infectious person. The activity level, position of occupant and arrangement of air supply and exhaustgrills in design spaces were investigated. It also investigated the ability of the ventilation system to reduce the risk ofinfection inside such rooms. Six different cases of an office room were studied in this work. The aim of the current workis to investigate which configuration is the best for reducing the danger of infection, besides temperature, velocity andrelative humidity distributions. The sixth case which contains partition wall and supply airflow from the floor showedthe best control of infection between all cases and good thermal comfort.