The reconstruction of PROPELLER MRI data is a typical reconstruction of non-Cartesian data.The sampling den-sity compensation in the current gridding reconstruction is accomplished through the convolution of non-Cartesian data,which re-quires calculating a large number of distances between each other non-Cartesian positions when the number of data is large such as PROPELLER.Therefore the density compensation is highly computationally intensive.In this paper,a new algorithm was proposed for density estimatio...