Herein, we propose a high-resolution C-band tunable fiber laser based on an echelle grating and a digital micromirror device (DMD). By employing the wavelength tuning performance of DMD and the high-resolution characteristics of an echelle grating, we design a cross-dispersion structure based optical alignment system, realizing the high-resolution wavelength tuning capability. Experimental results show that the laser demonstrates flexible tuning in 1542-1558-nm region by remotely loading holograms onto the DMD. The wavelength tuning resolution is approximately 0.036 nm, and the 3-dB linewidth of the output signal is less than 0.02 nm. The side-mode suppression ratio exceeds 40 dB, the center wavelength drift is less than 0.013 nm, and the power fluctuation is less than 0.07 dB within 1 h at room temperature.