Photoperiod is one of the most important environmental factors which affect the plant growth and development. Understanding physical requirements of a plant is essential for getting better yields. An attempt was made to study the effect of photoperiodism on different growth characteristics of Solanum lycopersicum. The study helps to identify the most suitable light period for a plant for getting better yield. By understanding the growth characteristics of a plant, they can be modified by using biotechnological techniques enabling them to be grown under a wide variety of environmental conditions. Results can provide theoretical basis for variety breeding and cultivation practice improvement in tomatoes.