To provide a playground equipment diagnostic system capable of conducting a routine safety evaluation for a playground equipment quantitatively and objectively.

One or a plurality of vibration generating devices 2 and a vibration detecting device 3, and a playground equipment diagnostic device 4 are provided. The vibration generating device 2 vibrates a fixed post 51 and beam 52 in the playground equipment 5 having the fixed post 51 and beam 52, and the vibration detecting device 3 is configured so as to output an electric signal in accordance with the vibration of the fixed pole 51 and beam 52. The playground equipment diagnostic device 4 is configured so as to conduct a frequency analysis of the electric signal, diagnose the state of the fixed post 51 and beam 52 by comparing the measured data thus obtained with a standard data 42B prepared beforehand and output the diagnostic result.