Optical metamaterials present opportunities and challenges for manipulation of light. However, metamaterials with visible and near infrared responses are still particularly challenging to fabricate due to the complex preparation process and high loss. Here, a visible light poly(amidoamine) (PAMAM)-Ag metamaterial is prepared with the assistance of fifth-generation PAMAM (5G PAMAM), based on the dendritic structure. The large area of metamaterials, where Ag nanoparticles are spherical with diameters of $\sim 9\mathrm{nm}$ and distributed in a multilevel netlike sphere, results in broadband resonance. The negative Goos–Hänchen shift and anomalous spin Hall effect of light generated by 5G PAMAM-Ag in visible broadband are observed, and a strong slab focusing effect at 750–1050 nm is demonstrated. In addition, the simulation shows possible application of the dendritic structure in topological photonics. The results offer advances in the preparation of large-scale visible light metamaterials, showing the potential for subwavelength super-resolution imaging and quantum optical information fields.