In modern engineering construction, the design of concrete mix proportion is very important, and its quality directly affects the quality and durability of buildings. This article conducts in-depth research on the combination of genetic algorithm and simulated annealing algorithm based on the actual needs of concrete engineering. And the performance of the two methods under various environmental parameters was compared, and their advantages and disadvantages were given. This article intends to conduct research using methods such as algorithm comparative analysis, experimental verification, and model validation. The research results of this article will help improve the scientificity and accuracy of concrete structure design, and also provide new ideas and methods for the optimization of practical engineering. The number 1 (Genetic Algorithm, GA) cement is 340 kg, sand is 720 kg, and the cost is 280 yuan. The cement with serial number 5 (simulated annealing algorithm) is 350 kg, sand is 710 kg, and the cost is 285 yuan. Therefore, the research results of this article will provide new ideas and methods for the design and construction of concrete structures in China.