In order to analyze the effects of strain rate and stress level on dynamic compressive strength, elastic modulus and critical strain of China railway track system（CRTS） Ⅰslab track cement asphalt mortar（CA mortar）, uniaxial compression test of CA mortar specimens of stress levels of 0%, 30%, 60% and 90% with strain rates ranging from 1×10-5s-1 to 1×10-2s-1 was carried out. Results show that the dynamic compressive properties of CA mortar are affected significantly by strain rate and stress level. The dynamic compressive strength of CA mortar increases with increase of strain rate, but decreases with increase of stress level, and the largest reduction of average dynamic compressive strength is 678%. The elastic modulus of CA mortar increases with increase of strain rate and stress level. The critical strain of CA mortar increases with increase of strain rate, but decreases with increase of stress level, and the effect of strain rate on the critical strain of CA mortar is greater than that of stress level.