An experimental research on interference of two risers with suppression device was conducted. The arrangement of the two risers is side-by-side, one is bare and another is a riser with triple strakes. Centre-to-centre distances from 3 to 10 diameters of the risers were studied. The riser model was a 18mm diameter organic glass with wall thickness of 2 mm. The current velocity ranges from 0.3 to 0.8 m/s, with approximate increments of 0.1 m/s. Dynamic strain records were obtained through the dynamic strain gauges which were sticked on the surface of the risers. The experimental data were contrastive studied by dynamic response, amplitude and frequency, respectively. The experimental results indicate that interference have little effect on the oscillatory characteristic of the riser with triple strakes while have important effect on the oscillatory characteristic of the bare riser with different distances.