A method for preparing an ecological foamed ceramic from lepidolite filter mud whole waste belongs to the field of environmental protection and resource reuse. The ecological foamed ceramic with excellent properties can be prepared by using lepidolite filter mud as the main raw materials, including ball milling, homogenization, drying, material distribution, and heat treatment. The amount of lepidolite filter mud in the present invention accounts for more than 90%, which is a whole waste utilization and can achieve high-value utilization of bulk lepidolite filter mud. The present invention uses a composite foaming agent combined with a foaming technology and has the advantages of rapid foaming and controllable pore size compared with a single foaming agent. The ecological foamed ceramic prepared by the present invention meets the industrial standard of CJ/T 299-2008 “Artificial ceramic filter material for water treatment” and has potential application value in domestic sewage treatment.