Provided is a camera optical lens including seven lenses sequentially from object side to image side: first lens having negative refractive power, second lens having positive refractive power, third lens having positive refractive power, fourth lens having positive refractive power, fifth lens having negative refractive power, sixth lens having positive refractive power, seventh lens having negative refractive power and with object and image side surfaces being free-form surfaces. Focal length of camera optical lens is f; focal length of first lens is f1, focal length of third lens is f3, focal length of fourth lens is f4; refractive index of third lens is nd3; refractive index of sixth lens is nd6; refractive index of seventh lens is nd7, and following relational expressions are satisfied: −1.52≤f1/f≤−1.38; 1.56≤nd3≤1.59; 1.53≤nd6≤1.81; 1.61≤nd7≤1.67; 2.04≤f3/f4≤2.27. The camera optical lens has excellent optical characteristics, and has large aperture, wide field of view, ultra-thinning and low optical distortion.