The co-pyrolysis characteristics and the interaction with a kind of low-rank coal from SunJiaCha mining area (SJC) and coking coal (Chinese pinyin for coking coal is Jiaomei, JM) from HuangLing were investigated using thermogravimetric Fourier transform infrared (TG-FTIR) analysis and gas chromatography-mass spectrometry (GC-MS). The results revealed a significant synergistic effect of the SJC+JM co-pyrolysis process The addition of JM increased the number of colloids and provided the conditions for the interaction reaction among the pyrolysis products. SJC and JM were used as hydrogen donors, the [H] and free radical fragments from pyrolysis facilitated the hydrogenation reaction. In addition, the composition and structure of the gas were changed due to the synergistic effect, which also substantially decreased the light component in tar substantially.