Nd³⁺-doped Sr_0.7La_0.3Mg_0.3Al_11.7O₁₉ (Nd∶ASL) single crystal fibers with different Nd³⁺ concentration were successfully grown by the micro-pulling-down (μ-PD) method. The crystal structure, polarized spectroscopic properties and continuous wave laser performance were studied. The Judd-Ofelt parameters Ω₂, Ω₄ and Ω₆ are obtained to be 1.093×10^-20, 2.285×10^-20 and 2.117×10^-20 cm², respectively. The fluorescence lifetime of 0.5%, 1.0%, 3.0% and 5.0% Nd∶ASL single crystal fibers are 375, 398, 384 and 363 μs, respectively. A continuous wave laser is obtained by pumping with a commercial laser diode of 800 nm emission wavelength. The maximum output power is 1.08 W at 1 055 nm with a slope efficiency of 18.5%. All the results indicate that Nd³⁺-doped ASL single crystal fiber grown by the μ-PD method has potential as a laser gain medium for laser system.