It generally takes 3-15 years to finish volatilizing formaldehyde, which is related to many factors such as the selection of materials for house decoration, indoor air circulation, the number of green potted plants that assist in removing formaldehyde, and indoor temperature. The main source of formaldehyde in the home is the decoration materials, formaldehyde volatilization rate and indoor temperature is significantly positive correlation, the higher the temperature, the faster the formaldehyde play. And indoor formaldehyde concentration and indoor ventilation time is a significant negative correlation, that is, the better the indoor ventilation conditions, the longer the ventilation time, the lower the concentration of residual indoor formaldehyde. In addition, indoor greenery has a significant effect on the removal of formaldehyde, such as greenery, aloe vera, ivy, agave, hanging orchids, etc., have the ability to remove formaldehyde. Therefore, raising indoor temperature, extending indoor ventilation time, increasing indoor green plants and other measures are conducive to the volatilization of formaldehyde. In short, how long can formaldehyde evaporate can not be generalized, the new room is recommended to be ventilated for six months to one year, and then choose to move in after testing to meet the standards, to prevent the concentration of formaldehyde is too high, causing harm to human health.