In order to improve the detection efficiency of the compaction quality of rock fill subgrade， the portable falling weight deflectometer(PFWD)and water bag method was used，based on the representative rock fill subgrade at the TJ09 test section of the Guangzhou Lianyungang Expressway. The regression model for the resilience modulus，resilience deflection and porosity of rock fill subgrade was established. The rapid method of the PFWD was explored to detect the compaction quality of rock fill subgrade.The results show that the correlation coefficient(R₂ )between the resilient modulus and porosity is greater than 0.7，and them show a good correlation. The variation coefficients of of the resilient modulus and the resilience deflection are 16.7% and 19.0%，respectively. Those indicate The dispersion degree of resilient modulus is smaller and more stable than that of rebound deflection.The PFWD is proposed as a fast method for the detection of compaction quality of stone-filled roadbed