An image pickup optical lens assembly, sequentially arranged from an object side to an image side along an optical axis, comprises the first lens element with positive refractive power having a convex object-side surface, the second lens element with negative refractive power having a concave object-side surface and a convex image-side surface, the third lens element with refractive power, the fourth lens element with positive refractive power having a concave object-side surface and a convex image-side surface, the fifth lens element with negative refractive power having a concave image-side surface with at least one inflection point, and a stop. Each of the five lens elements may be made of plastic with bi-aspherical surfaces. Additionally, the image pickup optical lens assembly satisfies conditions of shortening the total length and reducing the sensitivity for usage in compact cameras and mobile phones with camera functionalities.