The invention relates to a piling method in coal yards based on coal petrography and genetic algorithm. The technical scheme includes a first step of determining the random distribution ratio of reflection index of the vitrinoid group of coal piles in the coal yard, and determining the random distribution ratio of reflection index of the vitrinoid group of incoming coal, a second step of establishing a mathematical model for the fitness of piling in coal yards (i)Fitness(/i),a third step of using the genetic algorithm and mathematical model for fitness of piling in coal yards to seek for the optimal coal yard piling scheme, and a fourth step of using the mathematical model for fitness of piling in coal yards (i)Fitness(/i) to obtain the fitness of the optimal piling scheme according to the optimal piling scheme; if each overlap ratio in the fitness of the optimal piling scheme is >= 30%, the piling scheme can meet the production requirement; if certain overlap ratio in the fitness of the optimal piling scheme is < 30%, the third step shall be repeated. Overlap ratio of the random distribution ratio of reflection index of the vitrinoid group of coal piles and incoming coal of the coal piles is taken as the mathematical model for fitness of piling in coal yards, which has the advantages of simplicity, high efficiency, and fast optimization.