Indoor secondary organic aerosol (ISOA) formed from volatile organic compounds (VOCs) in indoor environments has been considered as one of indoor air pollutants. This study focused on the ultrafine particle formed by VOCs emitted from housekeeping products such as wax, air freshener and moth-repellent on the condition of ozone emission or UV irradiation with nitrogen oxides in the screening experiments, VOCs volatilized in the gas bag were added to ozone, and ultrafine particles formed by the chemical reaction were detected. Moreover, nitrogen oxides and UV irradiation could affect to form organic aerosol in a residential room. To focus on the unique indoor condition, secondary organic aerosol formations from pdichloro benzene emitted from moth-repellent were measured in the residential room. As a result, secondary aerosol formation from VOCs emitted from moth-repellent could not be observed on the exposure of the typical ozone concentration in the bag experiment. UV irradiation enhanced particle formation during adding ozone. And obvious particle formation was observed when repellents were put and nitrogen oxide gases were added in indoor environment.