An electrostatic precipitator (ESP) has been developed for collecting aerosol samples for attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) from an aerosol chamber. The ESP deposits the aerosol particles directly onto the ATR crystal with high efficiency. The ESP-ATR spectra are observed to agree well with the spectrum of a filter sample, transferred by impression. ZnSe ATR crystals have been found most suitable for electrostatic precipitation due to surface hardness, transmission characteristics and deposition behavior. ESP-ATR-FTIR spectroscopy might be a powerful tool not only for in situ but also for online measurements of aerosols.