The invention relates to a BIM technology-based kitchen, bathroom, balcony and room decoration deepening design method. The method comprises the steps of selecting a house main body BIM model according to the original two-dimensional drawing of any house; creating a kitchen, bathroom, balcony wall and floor tile arrangement model according to the BIM main body model and the kitchen, bathroom, balcony and room decoration scheme; determining whether the kitchen, bathroom, balcony wall and floor tile arrangement model conforms to the drawing, the specification and the on-site construction condition; if yes, drawing the electromechanical pipeline according to the kitchen, bathroom, balcony wall and floor tile arrangement model, pre-burying a wire box, and creating a civil engineering decoration integrated model; determining whether the civil engineering decoration integrated model accords with an electromechanical professional drawing and specification, and if yes, drawing according to thecivil engineering decoration integrated model, and obtaining a deepened design drawing. The method provides an integrated design of all fields, the collaborative operation of the design party and theconstruction party can be realized, the phenomenon of reworking caused by collision of the fields in the construction process is effectively avoided, the construction and arrangement are more reasonable, and the construction efficiency is improved.