The square-post hydrophobic surfaces with different roughness were prepared with the polydimethyl-siloxane (PDMS) substrate using photolithography techniques.The wetting characteristics were analyzed by measuring the superficial contact angles (CAs) of different surfaces.The experimental results show that the height of the micro pillars has a little effect on the CAs but affect the stability of wetting state on microstructured hydrophobic surfaces obviously.When the pitch and spacing are fixed,the stability of droplets becomes weaker with the decrease of the height.Moreover,the wetting characteristics were studied at different temperature.It is found that the CAs have a tendency to grow bigger with the temperature increasing from the dew point temperature to environment temperature,and from environment temperature to boiling point,the changing trend appears in opposite direction.The results suggest that the reasonable microstructure size and suitable environmental temperature have great significance on the stability of the wetting state.