Helical structure plays an important role in many fields and the machining quality is important for its applications. In this paper, a kind of functional hollow lightweight metallic micro-helixes based on cells of spirulina was manufactured by bio-limited forming. Then the impurity degree and the un-metallization degree, two important parameters to evaluate the machining quality of the functional micro-helixes in the application to chiral microwave absorbing material were investigated. Numeric models were established and the regularities were researched on how the two parameters are influenced by metallization technology factors. The results showed that the values of these two parameters could be reduced by adjusting the volume of the original deposition solution for 1g filtered wet activated cells, the diluted multiples of the original deposition solution, the temperature of reaction and the time of reaction so as to improve the machining quality.