The invention belongs to a building material and particularly relates to an algae calcium compound material, a decorative panel and a production method. Kieselguhr and a calcium-containing inorganic building material substrate are hydrated, gelled and compounded, thereby forming the algae calcium compound material, wherein the calcium-containing inorganic building material substrate is selected from one or more of hemihydrate calcium sulfate, calcium phosphate and calcium aluminate; preferably, the components are mixed at a weight ratio of the calcium-containing inorganic building material substrate to kieselguhr to enhanced fiber chopped strand to water-based gel solution to chemical auxiliaries being 100:(10-50): (1.2-2.0): (50-65): (5-10); and the raw materials are subjected to raw material pretreatment, mixing and stirring, filling and molding, maintaining and drying, and surface treatment, thereby forming a decorative material product. The excellent plasticity and environmental friendliness of the novel compound material are fully excited while the microporosity of the kieselguhr is utilized to endow the material with excellent functions of humidifying and absorbing harmful gas, such as, formaldehyde, and the like, and the environmental protecting functions, such as sterilization, and the like.