The invention discloses a rhombus cloth filter mounting method. A water outlet wall hanging form is adopted to connect with a water pool; and non-shrinkage grouting materials are filled between fixed angle steels and walls of the water pool. The method can be used for mounting whole sets of rhombus cloth filter equipment with various specifications, and has the advantages of high sewage treatment capacity, low cost, capability of forming flow operation, improvement of work efficiency, reduction of erection time, energy conservation, environmental friendliness and high promotion and application benefits.