New Jersey guardrails are the most commonly used form of guardrail in highway median strips due to their excellent safety protection. In response to the cost reduction and quality improvement, efficient and rapid preparation process, and quality issues of New Jersey precast guardrails, this article adopts the New Jersey precast guardrail automation production process to study the optimization of concrete mix ratio and its performance for precast guardrails. The experimental results show that in the designed C30 concrete, the compressive strength of the concrete mixed with 15% fly ash reaches 39.2MPa and the slump reaches 189mm, and the concrete performance meets the requirements of the fabric; Compared with the compressive strength of concrete formed by traditional vibrating rods and integral vibrating tables, the compressive strength of concrete formed by integral vibrating tables at all ages is higher than that formed by vibrating rods, and the coefficient of variation is smaller; The concrete formed by the overall vibration table has a smaller electrical flux at each age and better resistance to chloride ion penetration. Research has shown that adjusting fly ash to optimize the concrete mix proportion, combined with the application of overall vibration compaction technology, reduces concrete porosity and pore size, improves the compressive strength and durability of concrete, and can efficiently and economically obtain concrete that meets the high-performance requirements of guardrails, which has engineering application value.