Prime objective of this lecture is to present on Plants Life cycle. This is tutorial based lecture focus on Cyanobacteria: Blue- green algae. DNA of green algae shows the first green plants evolved from prokaryotes between 2500 and 1000 million years ago. Here also focus on Endosymbiosis; it is a symbiotic relationship between two organisms in which one of the two organisms lives inside the body of the other one. Finally present on Nonvascular life cycle, Seedless vascular life cycle, Gymnosperm life cycle and Angiosperm life cycle.