Photoluminescence (PL) steady-state spectra of p-ZnGeP2 (ZGP) single crystals grown by high- and low-temperature directed crystallization have been investigated. It is determined that the long-wavelength component PL with a maximum in the interval 1.2–1.5 eV for different crystals quenched in the temperature range 77–300 K. The long-wavelength component PL are due to donor-acceptor pair transitions. At room temperature the short-wavelength PL with a maximum near 1.85 eV becomes the determining component. The nature of this band discussed. The use of low-temperature directed crystallization reduces the concentration of lattice defects in ZGP single crystals and opens up the new possibilities for increasing the conversion efficiencies of nonlinear devices.