The invention discloses a 
boron-doped stress bar for manufacturing a polarization-preserving 
fiber and a manufacturing method for the 
boron-doped stress bar. The manufacturing method comprises the following steps of: A10, depositing a 
boron doping area on the inner wall of a 
quartz liner tube by using a 
plasma chemistry vapor deposition (PCVD) process to obtain a prefabricated member, namely introducing 
mixed gas into one end of the 
quartz liner tube, and discharging the 
mixed gas through the other end of the 
quartz liner tube, wherein the 
mixed gas comprises 
silicon tetrachloride vapor with the flow of 700-1,900sccm, high-purity 
oxygen with the flow of 1,600-5,000sccm and boron 
chloride with the flow of 70-1,100sccm; and A20, performing high temperature collapsar on the deposited prefabricated member into a 
solid boron-doped stress bar. BCl3 and SiCl4 are used as raw materials, the 
boron doping area is deposited at high speed and high efficiency by the PCVD process, and the 
utilization rate of the raw materials and the 
doping concentration are improved; and moreover, gradient 
doping is adopted, so that the problem that the boron stress bar is easily broken and twisted in the 
processing can be solved, the 
geometric symmetry of the doping area is improved, the probability of panda eye and cladding breakage in the 
cutting is reduced, and the 
welding efficiency of the 
fiber is improved.