A variable valve apparatus of an internal combustion engine adopts a structure in which, a transmission arm is laid out such that, when a distance from a contact point where a cam contacts a transmission arm to an oscillating fulcrum of the transmission arm is defined as A, and a distance from the oscillating fulcrum of the transmission arm to a point of action of the transmission arm is defined as B to thereby determine a B/A value, .theta.1 as a B/A value at the time of a high valve lift control for controlling valve lift characteristics, and .theta.2 as a B/A value at the time of a low valve lift control for controlling valve lift characteristics establish a relation of .theta.1>.theta.2.