Directing of a building in general and the architectural space in particular are important elements for designers to achieve an environmental equivalence and an effective functional activity within the architectural space. Schools of the modern era have to provide a lightening that provides a positive educational environment and helps towards a better education. Good lightening can adjust the mood of students, can rectify the behaviors, boost the concentration and attention level, stimulate those elements responsible on learning and attain an eye comfort. In this study, a simulation work on the lightening within a space of a classroom for a sample of basic education schools in the city of Al-khoms-Libya using DIAL ux evo 5 programs is reported. This study focuses on the period of activity in a classroom during three different times, at 08:00 am, 12:00 pm and 04:00 pm on 22 of June at which the sky is clear and shiny and represents the nearest point to the North in the path of sun.The space of the classroom was divided into three axes or regions represent the rows of students which are located near to the window(s), the intermediate one and the far one from the window(s). The horizontal simulation surface work is the surface of the tables of students at 0.65 m in height from the ground of the space. Similarly, the vertical simulation surface work is the blackboard of the classroom, since these two surfaces can be the most best scale to measure the good vision and the standard of the visual comfort of students in the classroom. The simulation was carried out in all different directions, main and secondary ones. It was also aimed to ascertain the levels of lightening and those times at which the sun penetrates the space and its effect on the visual comfort of students. Also, ascertaining advantages and disadvantages of each direction in order to find the most optimum solutions of each direction. The simulation process is carried out through not changing all those variables that may have an effect on the lightening intensity of a chosen sample but changing the direction of windows of the classroom to a different direction in each simulation process. Comparison and analysis of results, according to those standards that guarantee visual comfort inside the space with respect to standard lightening intensity according to international organizations and variation in the lightening levels and cases of dazzling, were made. According to what previously mentioned, results and recommendations can be made