The Ministry of Health, Labour and Welfare, Japan, had set guidelines for concentrations of indoor air pollutants such as di-n-butyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP) and the insecticides fenobucarb, diazinon, and chlorpyrifos, which are semi-volatile pollutants in indoor air. The Committee on Indoor Air Pollution, Japan, is reviewing the 20-year old indoor air quality guidelines. Therefore, the current levels of semi-volatile pollutants in indoor air must be established. Insecticides and phthalates are estimated separately, necessitating more efficient analytical methods. We developed a gas chromatography-mass spectrometry for simultaneous analysis of insecticides and phthalates using a cartridge composed of a quartz filter and a styrene divinylbenzene copolymer and applied it to a field survey. The recovery and relative standard deviations (RSD) for the insecticides' were 97.4–103% and 3.58–9.65%, and those for phthalates were 87.4–102% and 1.35–8.22%, respectively. The limits of quantitation (LOQ) for chlorpyrifos, diazinon, and fenobucarb were less than 1/10 of guideline values at 0.0128, 0.0201, and 0.00667 µg/m³, respectively. The LOQs of phthalates were 0.0882 µg/m³ for DBP and 0.107 µg/m³ for DEHP, each less than 1/193 and 1/935 of guideline values, respectively. The simultaneous analysis method was used to survey residential houses. Insecticides were not detected in the indoor air of residential houses. In contrast, phthalates, diethyl phthalate (DEP), DBP, and DEHP were detected, and their concentration distributions decreased from those found in the 2000s.