A field experiment was carried out in Faculty of Agriculture Farm, Al-Azhar University, Assiut, Egypt during two successive seasons 2018/2019 and 2019/2020 aiming to study the effect of four rates of vermicompost (zero, 2, 4 and 6 tons /feddan) (feddan = 4200 m² = 0.420 hectares = 1.037 acres) and three concentrations of chitosan nanoparticles (ChNP) at zero, 20 and 40ppm, as well as, their interaction on growth, yield and chemical constituents of black cumin (Nigella sativa L.) plants.The obtained results showed that all vermicompost levels increased plant height, branch number, herb fresh and dry weights, capsule number and weight/plant, seed weight/plant, 1000 seed weight, fixed and volatile oil percentages and yields and NPK percentages in herb. However, the high rate of vermicompost (6 tons /feddan) gave the best results for these characteristics. Also, treat plants with all concentrations of chitosan nanoparticles (ChNP) showed significant increases in all parameters, except 20 ppm in the second season, regarding branches number comparing to control. The best results were obtained by 40 ppm ChNP in comparison with control. The combined treatment of vermicompost (6 tons /feddan) with 40 ppm ChNP recorded the best results of most parameters.