Compared with the extensively studied MoS₂ and WS₂, WTe₂ owns a smaller bandgap, which is applicable to a near-infrared system in photodetectors, communications, and ultrafast optics. In this work, the WTe₂ saturable absorber (SA) with the tapered fiber structure is prepared by the magnetron-sputtering technology, which enables the prepared SA to be low in cost and have strong nonlinearity. The modulation depth of the prepared WTe₂ SA is measured as 31.06%. The Q-switched fiber laser operating at 1.5 μm is successfully investigated by incorporating the proposed SA into the prepared ring cavity. To the best of our knowledge, this is the first attempt of WTe₂ in the Q-switched fiber laser at 1.5 μm.