The invention provides a method for obtaining a high resolution nuclear magnetic resonance heteronuclear spectrogram in an unknown spatial distribution magnetic field, and relates to nuclear magnetic resonance. According to experimental requirements, whether a signal to noise ratio or sampling efficiency is preferred is judged; if the signal to noise ratio is preferred, a three-dimensional sampling mode is used; if the sampling efficiency is preferred, a spatial encoding and decoding sampling mode is used; samples are obtained after sequential parameters are set, and experimental data are stored after the sampling is over; the stored experimental data are processed; if the experimental data in use are obtained through the three-dimensional sampling mode, the experimental data are constructed into a three-dimensional time-domain matrix, and an experiment spectrogram can be obtained as long as the matrix is subjected to three-dimensional Fourier transformation; if the data in use is obtained through the spatial encoding and decoding sampling mode, first, each data string with the length of np points is divided into np1*ND segments, then, the segments and indirect F3 dimensions form a three-dimensional matrix, and the high resolution nuclear magnetic resonance heteronuclear spectrogram can be obtained as long as the F2 and F3 dimensions of the three-dimensional matrix are subjected to Fourier transformation.