Abstract: According to the characteristics of marine data such as multimodal,high-dimension and magnanimity,this paper proposes an optimized sampling method for marine environmental monitoring data based on spatial correlation.With the water depth data of a sea as an example,the method is arguably analyzed by two perspectives,which are sample size and variance.At the same time,to verify the feasibility and validity of this method,this paper compares the inverting trend surface and actual trend surface,reduces the number of sampling data while ensuring the accuracy of sampling.