Objective To analyze 3D double-echo steady-state with water excitation MRI in lumbosacral nerves. Methods 30 cases for physical examination in April 2017 were selected as subjects. All cases received 3D double-echo steady-state with water excitation MRI in lumbosacral nerves. The maximum intensity projection of the thin layer and the multiplanar reconstruction of the original image of the two-dimensional bi-directional steady state water excitation sequence are carried out. Image was reconstructed. The left and right nerve display scores, the nerve length, length and width of the ganglion were evaluated. Results All the subjects were examined and no organic lesions were found. 3D double-echo steady-state with water excitation MRI showed that the lumbosacral nerves, spinal ganglia, and cerebrospinal fluid are high signals, skeletal muscle is medium signal, and bone, fat, and large vessels are low signals. The score of nerve, length of nerve, length and width of nerve between the right and the left nerve were not statistically different(P ＞0.05). The length of L5 nerve was the longest, followed by S1, L4 and S2. From T12 to S2, the ganglion width showed a gradually increasing trend, and from T12 to S1, the ganglion length showed a gradually increasing trend, and S2 has declined. Conclusion 3D double-echo steady-state with water excitation MRI in lumbosacral nerves can clearly show the nerve trunk, ganglia and so on.