The invention relates to a low-dielectric laser direct structuring composite material suitable for 5G communication. The composite material is composed of the following components in parts by weight:52 to 86 parts of base resin, 0 to 30 parts of glass fibers, 10 to 30 parts of a filling agent, 1 to 9 parts of a flame retardant, 4 to 15 parts of a toughening agent, 0.1 to 1 part of a lubricating agent, 0.2 to 1 part of an antioxidant and 10 to 30 parts of a laser sensitive additive. A preparation method of the composite material comprises the steps that a twin-screw extruder is used for processing, the melt extrusion temperature is 250-380 DEG C, and the screw rotating speed is 150-300 rpm/min. The composite material has low dielectric property, so that improvement of the transmission speed of 5G communication millimeter wave signals is facilitated, the signal delay is reduced, and the signal loss is reduced; the composite material has the LDS processing capacity, can be rapidly prepared in a small size and a large number, can be subjected to batch laser etching and chemical plating to form a metal connecting circuit, and is an optimal solution of a 5G plastic antenna oscillator material.