Lower-noise and higher-stability mode-locked lasers and frequency combs are becoming more important and useful sources for a variety of applications ranging from precision spectroscopy to photonic signal generation and processing. In particular, all-fiber-based sources have clear advantages such as low cost, alignment-free operation, lightweight, and long-term stability. In this talk, I will overview our recent progress in realizing ultra-stable and ultra-low-noise mode-locked fiber lasers and frequency comb sources.