When the transformer is overheated or has a discharge failure, characteristic gases such as C₁ and C₂ gases are dissolved in the insulating oil. There is also a small amount of C₃ component gases that may interfere with the detection of other characteristic gases. By analyzing the causes of gas cross-interference and the infrared absorption spectra of C₁, C₂, and C₃ component gases, the gas absorption coefficients within the filter bandwidth were studied and the interference coefficients of C₃H₈ and C₃H₆ gases to C₁ and C₂ gases were theoretically calculated. According to the analysis results, the parameters of the optical filters were determined. A photoacoustic spectroscopy based multi-component gas analysis system using infrared thermal radiation source and non-resonant photoacoustic cell was built. The experimental results show that the interference coefficient of C₃H₈ gas to CH₄, C₂H₆, C₂H₄, C₂H₂ is 3.78%, 84%, 1.5% and 1.6%, respectively. The interference coefficient of C₃H₆ gas to CH₄, C₂H₆, C₂H₄, C₂H₂ is 2%, 32%, 69.6% and 2.6%, respectively. This research is of great significance for evaluating and guiding the improvement of the technical performance of photoacoustic equipment for dissolved gas analysis in transformer oil.