Abstract—In this study, we present the respective calibration set up and procedure with serial connection for dew point hygrometers with chilled mirror and aluminum oxide types. To evaluate in more detail the response characteristics according to dew point hygrometers by connection order in series, the variation of measured dew point temperatures and uncertainty contribution rate due to the connection order of hygrometers were investigated for two types of hygrometers the most widely used. We suggest treatment method for measurement deviation caused by multiple series connection and appropriate connection method due to dew point hygrometer types. The calibrations were conducted according to standard calibration procedure of Korea Testing Laboratory accredited from ILAC (International Laboratory Accreditation Cooperation) and KOLAS (Korea Laboratory Accreditation Scheme).