The present invention refers to a composition, a low halogen and fast curing conductive adhesive and its preparation method. The composition includes the following raw materials measured by weight: epoxy resin 5-15 parts, curing agent 0.5-3 parts, acrylic acid component 5-12 parts, initiator 0.5-2 parts, flexibilizer 2-5 parts, wetting dispersant 0.1-1 parts, coupling agent 0.1-1 parts, antioxidant 0.1-1 parts, defoamer 0.1-1 parts and conductive silver filler 75-85 parts. The low halogen and fast curing conductive adhesive of the present invention has the advantages of fast curing (within 10 min), low halogen content, high bond strength, good moisture-heat aging resistance, good electric conductivity and thermal conductivity and so on, and has wide application prospects in the field of microelectronic packaging.