To investigate the relationships among Sick Building Syndrome (SBS) symptoms, we conducted a questionnaire and an indoor environment mold survey in a sample of newly built dwellings in Japan. The questionnaire included questions on SBS symptoms and lifestyle and a mold survey conducted in the living room of each dwelling. The odds ratios (OR) for insufficient sleep were 3.58 in males and 2.57 (weighted for SBS symptoms; W) in females, 0.38 (W) for alcohol consumption in males, and 0.10 (W) for working hours in females. The ORs for total molds were 2.90 and 2.90 (W): 2.25 (W) for Cladosporium cladosporioides, 3.60 and 7.69 (W) for Penicillium sp. in females, and 4.08 and 8.82 (W) for Alternaria alternata in males. These results suggest that the presence of Penicillium sp. in females and Alternaria alternata in males increases the risk of SBS, whereas sufficient sleep, moderate alcohol consumption for males, and fewer working hours for females might alleviate SBS symptoms.