The invention discloses a joint optimization method of safety capacity and energy consumption in a wireless relay network, and relates to the field of wireless relay network cooperative communication. The method comprises the steps as follows: a safety capacity value from a source node to a destination node is restrained to be SCcon; a minimum energy consumption function of an interference node is obtained by using a beam forming technology according to the SCcon; a minimum energy consumption function of a relay node is obtained according to the SCcon; a minimum energy consumption function Dpower of a system is obtained; a minimum energy consumption value Pmin of the system is obtained at an extreme point of a minimum value of the Dpower, and the restrained safety capacity is released; and an efficiency function RSE of the system energy consumption is calculated. The invention provides a joint optimization strategy of the relay node and the interference node, and an accurate expression of equivalent safety capacity maximization corresponding to the unit energy consumption of the system is obtained, so that each part of energy reaches the maximal usage value, and the problem of balance between the safety and the energy efficiency in the wireless relay network under a single sniffing node is effectively solved.