The invention discloses a pretreatment technology of the surface metal plating oftitanium alloy and a metal plating method adopting the pretreatment technology. The pretreatment technology comprises the following steps: performing alkaline degreasing on the titanium alloy, soaking the titanium alloy in H2C2O4 solution at the temperature of 80 DEG C, performing eroding treatment with ultrasonic wave for 3 hours, activating by use of an efficient ionic palladium activation treatment agent for 1-2 minutes, and performing chemical reduction for 30-60 seconds to perform metal plating. The metal plating method comprises the following steps: placing the pretreated titanium alloy in an acidic solution at the temperature of 80-90 DEG C to perform metal plating for 2-3 hours, taking the alloy out, rinsing to obtain Ni-P, Ni-B and Ni-P/Ni-B alloy platings, and drying at 250-350 DEG C for 30-45 minutes to obtain the finished product. The metal plating pretreatment technology of the titanium alloyhas the advantages that the process is simple, the method is environmentally-friendly and fluorine-free, the treatment liquid can be used repeatedly and circularly, and the like.