We report on our first results of a dispersion-managed monolithic polarization-maintaining ultrafast Thulium-doped fiber oscillator. The design incorporates only commercially available polarization-maintaining components and emits linearly polarized light with a polarization extinction ratio of over 17 dB . The observed optical pulse spectra with up to 10 nm width centered at 1961.5 nm beyond the water absorption lines support sub-1 ps pulse duration. The simple linear configuration and the wide spread availability of the used low cost polarization-maintaining fiber components makes the presented oscillator a valuable concept for an environmental stable seed source.