The invention provides a plane two-freedom-degree parallel mechanism. A first connecting rod, a second connecting rod, a third connecting rod, a fourth connecting rod, a sixth connecting rod and a seventh connecting rod are sequentially connected through rotary pairs, one end of a fifth connecting rod is connected with the fourth connecting rod and the sixth connecting rod, the other end of the fifth connecting rod is connected with one end of an eighth connecting rod through a rotary pair, the other end of the eighth connecting rod is connected with the seventh connecting rod and the first connecting rod, one end of a ninth connecting rod is connected with the sixth connecting rod and the seventh connecting rod, a first sliding block and a second sliding block are connected to the ninth connecting rod through a first movable pair and a second movable pair, the second rotary pair for connecting the second connecting rod and the third connecting rod is fixed to the first sliding block, and the second rotary pair for connecting the fifth connecting rod and the eighth connecting rod is fixed to the second sliding block. The first connecting rod is equal to the fourth connecting rod, the second connecting rod is equal to the third connecting rod, the fifth connecting rod is equal to the eighth connecting rod, and the sixth connecting rod is equal to the seventh connecting rod. The plane two-freedom-degree parallel mechanism has a symmetric structure, completely symmetric movement can be achieved, great convenience is brought to application and control of the mechanism, and wide application prospects are achieved.