An optical image capturing assembly includes four lens elements, in order from an object side to an image side, the four lens elements are a first lens element, a second lens element, a third lens element and a fourth lens element. The first lens element with positive refractive power has an object-side surface being convex in a paraxial region thereof. The second lens element has negative refractive power. The third lens element has positive refractive power. The fourth lens element with negative refractive power has an object-side surface being concave in a paraxial region thereof.