The latex organic molecular were characterized by fourier transform attenuated total reflection infrared spectroscopy (ATR-FTIR) in the temperature range 303~ 393 K. The C-H stretch vibration (ν_C-H)，C=C stretch vibration (ν_C=C), CH2 bending vibration (δ_CH2), CH3 bending vibration mode (δ_CH3) and C-H wagging vibration (ω_C-H) were found in the region between 3500 cm^-1 and 600 cm^-1. Two-dimensional infrared spectra of latex (ω^_C-H) were studied to determine the sequence of intensity changes. Actually two bands were observed: one at 837 cm^-1 and one at 841 cm^-1. It had been found that the sequence of intensity changes was 837 cm^-1 > 841 cm^-1 when the temperature increased. The study demonstrated the key roles of ATR-FTIR in the analysis of thermal denaturation of the latex.