Fiber lasers in the 2 μm band are widely applicated in biomedicine, environmental monitoring, nonlinear frequency conversion, as well as in laser radar and laser communications. However, the power scaling of lasers in this band are limited by low quantum efficiency, high thermal loading, and several nonlinear effect. In this study, we propose a higher-order phase modulation technique based on inverted probability tuning sequences to suppress the SBS effect, a signal laser time-domain stabilization control technique with multi-stage link auto-feedback to enhance the SRS threshold, and a fiber-based transverse-mode purification technique to control the beam quality. Finally, a two-stage main amplification structure is used to achieve an ultra-narrow linewidth near-diffraction-limited output of 1 kW at 1 950 nm, with an optical-to-optical conversion efficiency of 55.6%, linewidth of 3.8 GHz, beam quality M² factor of about 1.2, and no transversemode instability effect.