The Great East Japan Earthquake generated on March 11, 2011 brought damage to much of the northeast area of Japan. The required number of temporary houses is more than 50000. Many disaster victims will have to reside in temporary houses for the near to long term future. Mould contamination is expected to be an ongoing problem, especially given increased residential humidity resulting from the flood damage generated by the associated tsunami. Our study aims to assess indoor air quality related to mould contamination in temporary housing. This paper describes the results obtained in a survey of 40 temporary houses in Sendai-shi, Miyagi in August and October, 2011. Airborne and floor moulds were sampled by one-stage impactor and vacuum cleaner, respectively. Moulds were cultivated using DG18 culture medium. We report that in 40 tested houses, fungal concentrations exceeded 1000 cfu/m3 in 45 of 66 rooms (70%). Thus, indoor environmental fungal growth, especially by xeric fungi, may present a serious concern for residents of temporary housing.