The invasive fall armyworm (FAW), Spodoptera frugiperda has become one of the major pests of maize In India and various strategies need to be developed for its management. Currently, silicon (Si) is known to reduce damage caused by pests by inducing resistance and promote plant growth and development. There are many sources of Si and few of them are locally available which need to be tested for their efficacy in reducing the FAW damage. A field study was conducted to know the field efficacy of rice husk biochar (RHB) as a source of Si and imidazole, a Si solubilizer, alone and in combinations against FAW. Application of RHB at 4t/ha along with imidazole at 40.8 g/ ha was significantly effective in reducing the damage caused by FAW. Least number of larvae per plant (0.38), damage score (2.22) and per cent infestation (60.79) in was recorded in this treatment, as higher accumulation of silicon content in leaves (3.55%). The same treatment significantly influenced the vegetative characters such as plant height, stem diameter, shoot weight and chlorophyll content. The yield parameters viz., cob girth and test weight were also positively influenced which results in higher grain yield (65.89 q/ha) with higher Cost Benefit ratio of 1: 1.49, which was significantly higher than the other treatments. The study demonstrated that rice husk biochar and imidazole can therefore be integrated as one of the component in FAW management.