In the past two decades, various solution-based strategies have been developed by many groups to synthesize Te nanowire, including microwave-assisted process, electrochemical routes, etc. Among these methods, direct chemical reduction has been the most popular due to the considerably high yield and simple procedures, makes it promising method for large-scale production. However, a rational design for the shape and dimension control for the function devices is needed. Here, we report a systematic synthesis of high disperse and single crystal Te nanowire with controllable dimension. Besides, after assembling the tellurium nanowires on the stretchable substrates, a stretchable, soft piezoelectric nanogenerator has been developed with the capability to efficiently convert mechanical stimuli into electric power. We revealed the correlation between the piezoelectric outputs from the integrated devices and the diameters of as-produced tellurium nanowires, which establish process-structure-property-performance relationship in the piezoelectric nanogenerator that may pave way for the nanomanufacturing and practical application of piezoelectric nanomaterials.