Abstract: The presented system is a cost effective and energy saving mean of transmitting sunlight downward into a narrow alleys and streets, by using a day-lighting guiding acrylic panel that is capable of changing the direction and distribution of the incident light. The core of the proposed daylight guidance system is made up of light transmission panels that have sine wave shaped cross-section so that the panel functions as an optical diffusor perpendicular to the optical axis. The system consists of the panels and a lattice frame, which supports the panel. The proposed system is to be mounted on the building roof facing the sun but, since building sizes and orientations are different the frame is designed to be easily rotated to adopt different solar conditions such that substantially deep light penetration and high luminance level can be achieved.