We fabricated a three-dimensional nonlinear photonic crystal in a Sr_0.61Ba_0.39Nb₂O₆ (SBN) crystal using femtosecond laser direct writing of ferroelectric domain structures. The crystal features three layers of fork-shaped gratings, each oriented differently. These gratings convert an incident vortex beam into a second-harmonic Gaussian beam in specific directions. By altering the vortex beam’s topological charge, we can control the emission direction of the second-harmonic Gaussian beam, enabling flexible all-optical switching and manipulation. This work provides a foundation for controlling photon angular momentum in nonlinear optical frequency-conversion processes.