Abstract: A camera module having OIS function and its preparation method are provided. The camera module includes a housing and an optical assembly in the housing, and further includes a circuit board in the housing. The circuit board includes a first board and a second board on the first board. The first board is flexible. The first board includes a first portion, a second portion, and a third portion successively connected in an extending direction of the first board. The second portion defines a slot. The second board is on the third portion. The optical assembly is on the second board. The first portion includes a fixed end connecting the second portion and an opposite free end. The housing defines a through hole. The first portion extends through the slot to form a bent portion and extends out of the through hole, such that the free end is outside the housing.