Purpose: Evaluate human performance under LED lighting system in commercial building regarding:-Visual Performance (VP), Motor Performance (MP), Task Performance (TP), Cognitive Performance, Human Performance, and Work Life. To assess the direct effect between Cognitive Performance and Human Performance To identify the role of Circadian System (M1), and Discomfort (M2) between Cognitive Performance and Human performance. Theoretical framework: Driven lighting is presently the most reliable. As a result, determining all crops' light needs is complicated. Purposive sampling use to select the respondents. Floor office units and single office rooms required LED illumination. Because the entire population list was unavailable, 200 samples chose for the investigation. The study looked at an employee's cognitive and human performance. No relation between visual and cognitive performance. Pain impairs cognitive and motor functions. No discomfort affects work-life balance. However, the pain reduces human performance. Distress, eye pain, and weariness impede human performance. However, visual discomfort, visual message, glare, and flicker do. The study recommends assessing visual performance based on employee illumination discomfort. Design/Methodology/Approach:Driven lighting systems are now the most widely used and dependable in the world. Compact fluorescent light bulbs are used in India's current lighting systems for the most part. Even though there are a few small and medium-sized LED producers, there is no industry standard for LED production. As a result, estimating the amount of light all types of produce require is difficult. The goal of this research was to find out how LED illumination affects human performance. An organized questionnaire was utilized to gather information from employees of various government and commercial sector organizations. The research focused on the Trivandrum area because Trivandrum is Kerala's capital and home to most of the state's administrative offices. Respondents were drawn from government and private sector offices using a stratified random sampling approach. Offices were divided into floor office units and single office rooms, with LED lighting systems required in all of them. Two hundred samples were chosen for the study after the reliability and genuineness of obtained data were checked because the entire population list was unavailable. Findings: Research, Practical & Social Implications: As a result of this research, we set out to determine how well LED and conventional (linear fluorescent, compact fluorescent, and incandescent) lighting systems perform luminously, how well people perform, and how much they cost in the most common luminaire applications currently found in the environment. The popularity of LED lighting systems has overtaken that of all other kinds of fabricated luminaires. In contrast, linear and compact fluorescent luminaires are used in most Indian lighting systems now in use. No LED standards exist, despite just a handful of medium and small firms currently producing LED lights. As a result, establishing the precise illumination requirements for each product is challenging to do. Compare the environmental, technological, and economic factors to the alternatives now accessible to discover a better solution. Originality/value: Human performance is very much important in every sector and it’s depended on various multi-dimensional factors. Here the study has been analysed the direct and indirect effect between Cognitive Performance and Human performance of an employee. Simultaneously, study is saying that cognitive performance is not depending on the visual, and task performance. On the other hand, it could be seen that, Cognitive performance is affected by discomfort and the motor performance influence towards the Cognitive performance is positive but not significant. In the case of work life, it has no influence towards the human performance and also discomfort is influencing the human performance. While analyzing the mediation effect, it was found that, direct effect of Cognitive Performance will increase the Human Performance, but the existence of discomfort will reduce the human performance. Which means that negative mood change, visual discomfort, discomfort to visual message, Glare, Flicker, Eye pain, and fatigue are reducing the human performance. Based on the findings from the study, it could be seen that visual, motor and task performance is not influencing the cognitive performance, at the same time visual discomfort, discomfort to visual message, Glare, Flicker are decreasing their performance. hence, the study is suggesting that visual performance should be measure on the basis of various discomforts faced by the employee from their work place lightening.