According to characteristics of Loongson 3A architecture and BLAS level 2, this article derives the parallel solutions from instruction level, storage level and thread level. We summarize some suitable optimization methods and make a quantitative analysis. Experiment shows that the single-threading performance of BLAS level 2 is increased by 20%, and the multi-threading speedup reaches to 2.5. All of these will give some help to the optimization of system software on multi-core Loongson 3A.