The invention discloses a SiC matrix composite material element and the online connection and preparation method. The element is connected into a whole by the connecting piece through the connection layer at the connector lug, which is characterized in that the component of the connection layer is pure SiC material and the SiC material uses the mix solution of PCS and divinylbenzene as the adhesive, and uses SiC fine power as the packing medium, and can be achieved though preceramic polymer pyrolysis; SiC matrix composite material element with stronger connection strength can be gained throughthe auxiliary connection and the reinforcement of the fastener of SiC matrix composite material. The SiC matrix composite material element and the online connection and the preparation method has theadvantages of simple and practical preparation method, low cost, good thermostable performance and mechanics compatibility, good structural integrity. The connecting preparation method is especiallysuitable for the connection formation and preparation of large-scale complex components.