The application of seaweeds as muck in agricultural farming has been very common from ancient times in the Roman Empire, Japan, China, France, Spain, Britain, etc. Most coastal areas all over the world use seaweeds as bio-fertilizer for crop production. Seaweed extracts are used in different ways like seed treatment, foliar spray and soil application for plant protection and for plant growth promotion. Seaweed extract is more useful than chemical fertilizer because of its bio-decomposable, non-toxic and eco-friendly property. These are the most important reasons to use seaweed extracts in recent years for sustainable agriculture in organic and integrated organic farming. Seaweeds affect agricultural crops for enhancement of plant growth, seedling growth, both root hair and secondary root development. It can also improve nutrient incorporation, fruit setting, resistance properties against pests and diseases, improving the stress management (drought, salinity and temperature). The present review focused on use of seaweed extract in the agricultural system and novel strategies for the use of seaweed extract.