As a special art decoration, the objective mosaic pattern has left a deep impression on consumers and led the art trend with its rich visual experience. The work aims to research the ways to synthesize high-quality mosaic patterns. Firstly, the feature clustering analysis of material was extracted, and the initial mosaic pattern was synthesized under the guidance of the Gestalt theory. Then the proximity relationship and pattern layout of the mosaic pattern material were optimized, and finally a beautiful mosaic pattern was generated. Through the analysis of mosaic pattern synthesis effect and quality, the results showed that under the guidance of the Gestalt theory, discrete and irregular materials could generate layout patterns that met the visual effect. The pattern synthesis took 2-10 minutes. The composite pattern had the characteristic points of the original image. The spacing of the material layout was reasonable. The layout was orderly. The user evaluation score was above 90 points. Applying the generated mosaic pattern to packaging can bring users beautiful enjoyment at different distances and improve the product purchase rate. Under the guidance of the Gestalt principle, mosaic pattern synthesis and design can provide users with good visual experience, and the synthetic pattern has high artistic and economic value.