The paper presents results obtained from the dynamic load tests of the bridges for more than 50 year period. The main values obtained from the load testing are - the vertical displacement of the deck including dynamic load factor, the natural frequency of the bridge, the dynamic amplification factor and the logarithmic decrement. The obtained results show that the natural frequency highly depend on the length of the span, statical scheme of the bridge, type of the span cross-section, structural materials, construction methods, bearing type, etc. It was found that the dynamic amplification factor didn’t depend on the natural frequency, but was dependent on the logarithmic decrement. The logarithmic decrement showed dependency on the length and the types of the span structures.