Air side heat transfer and fluid flow characteristics of designed heat exchanger with bridge type fin were studied experimentally. The heat transfer and friction factor correlations were obtained in the experimental range of Reynolds number by processing a large number of experimental data. The experimental result shows that the heat exchanger with bridge type fin has greater heat transfer performance than the straight-fin heat exchanger under the same pump. At the same time， the air-side temperature and velocity field of these two kind fins were simulated by numerical method， and the results were analyzed by the field synergy theory， which shows that the heat transfer enhancement of bridge-type fins is caused by the improvement of the synergy between the velocity field and the temperature gradient.