A new method of three dimension shape measurement is presented. The random digital speckles are projected on the reference plane, which is moved by equal distance in the direction of depth. Temporal sequence speckle images are acquired with CCD as reference set R(t). Replace the reference plane by object, the speckle image O modulated by the object, is also grasped with CCD. The correlation value between any subimage O(x,y) in O and the corresponding subimages R(x,y;t) in R is approximately quadratic curve distribution. The position of the curve peak, is the height value of the object point. The method goes out of the limit of original horizontal correlation in previous method and is a true temporal sequence correlation method. It is a simple principle and higher measurement precision without complicated phase unwrapping and calibration procession, and can be used to measure the discontinuous and spatial isolation shape. According to the characteristic of error, a new interpolation method bas oncorrelation weight is presented. It has better result than normalinter polation method.