The traditional phase retrieval of in-line digital holography is invalid to eliminate the twin image and to get accurate phase when the object does not conform the sparsity, while the resolution of the off-axis digital holography is low due to the limitation of the minimum of the recording distance. An in-line and off-axis hybrid digital holography is proposed. The off-axis and in-line holograms are recorded respectively. The approximate phase distributions in the recording plane are obtained by constrained optimization approach from the off-axis hologram, and they are used as the initial value in the iterative procedure of the reconstruction of the in-line hologram, then the high quality amplitude and phase images are reconstructed. The ideal resolution of the hybrid digital holography is analyzed. The experimental results show that the proposed method can utilize the full spatial bandwidth of the image sensor, it can realize a large field of view and high resolution digital holographic imaging without the interference of the twin image when the objects have complex shape, and the resolution in the experiments approach the ideal resolution.