A positioner and a probe head of a probe card are provided. The positioner has a main opening, a first sub-opening, a second sub-opening, a third sub-opening, a fourth sub-opening, a first positioning portion, a second positioning portion, a first elastic portion and a second elastic portion. The first sub-opening, the second sub-opening, the third sub-opening, and the fourth sub-opening are sequentially arranged at the periphery of the main opening and are communicated to the main opening. A stiffness of the first positioning portion and a stiffness of the second positioning portion are higher than a stiffness of the first elastic portion and a stiffness of the second elastic portion.