The invention discloses a phononic crystal band gap simulation node integration algorithm, which comprises the following steps of: firstly, dispersing a single primitive cell by adopting a non-structural grid, and interpolating displacement by adopting a linear shape function; Then, constructing a corresponding smooth domain based on the nodes of the background grid, and introducing a gradient smoothing technology and a Taylor median theorem to carry out smoothing processing on the strain in the integral domain; On the basis, constructing a mass matrix and a rigidity matrix of the whole system; and finally, forming a corresponding eigenvalue problem equation by applying a Bloch periodic boundary condition. Compared with the prior art, the method has the advantages that the defect that a traditional finite element method model is too rigid can be effectively overcome, and the calculation precision and the convergence efficiency are improved. In addition, the algorithm also has the advantages of simple pre-processing and strong grid distortion resistance.