Using the measured wave data from January to June，2009 of the coastal station in the south of the northern Jiangsu radial sand ridges，we study the wave characteristics of the area.After taking all data for statistical analysis，we gain its wave height eigenvalues and explore the relationship between each characteristic wave height and mean wave height (significant wave height)；after screening out 25 sets of wavefront data，whose significant wave height occurs extreme time，calculate the wave height，period and between joint probability density distribution with probabilistic method and compare them with corresponding theoretical formula results.Statistical results show that Gluhovski distribution is more applicable to the wave height distribution in this region；when the spectral width is small，Longuet-Higgins theoretical cycle distribution fit in with the measured distribution better；when the wave height is big and the period is small，the measured joint probability distribution of wave height and period and each theoretical distribution are in good agreement.