The purpose of this paper is to investigate the applicability of thermoelectric cooling system (TEC) in dedicated outdoor air system (DOAS). As a promising non-vapor compression technology, thermoelectric cooling system can reduce the overall system size. In this paper the applicability of TEC was investigated as a substitution for chiller in conventional DOAS. As a heat dissipation system of TEC, air-cooled heat sink and evaporative-cooling heat sink was investigated. The coefficient of performance (COP) and energy consumptions were compared among conventional DOAS and two TEC integrated DOAS with different heat sinks. As a result the conventional DOAS have better performance than two DOAS with TEC. However the system size and electricity energy consumption of DOAS can be decreased when applied with TEC of low temperature difference between its hot and cold side.