[en] Highlights: • NaGdF₄:Nd³⁺ nanocrystals with different morphology were successfully synthesized. • Fundamental information about solvent composition dependent morphology was evaluated. • Photoluminescence spectra of NaGdF₄:Nd³⁺ nanocrystals were studied. • The nanotube-like nanocrystals showed excellent luminescent intensity and decay time. NaGdF₄ nanocrystals with controlled shapes were synthesized in an ethylene glycol/deionized water hydrothermal reaction system. Through adjusting the solvent composition, the nanocrystals with nanosphere-, nanotube-, and nanorod-like morphology have been selectively synthesized. The change in the nucleation speed, the growth rates in different crystallographic direction and the aggregation driving forces induced different morphologies of the resulting nanocrystals. A possible mechanism of shape evolution depending on solvent composition was proposed. Photoluminescence spectra of NaGdF₄:Nd³⁺ nanocrystals exhibited characteristic emission of Nd³⁺ using an excitation wavelength of 794 nm. Moreover, the nanotube-like nanocrystals exhibited the strongest fluorescence intensity and longest fluorescence decay time.