This book is the out come of one year research project under the guidance of Professors at Addis Ababa University. The author has made efferts to investigate the antifungal efficacy of herb and spice essential oils grown in Ethiopia. In the book, it was presented that thymus and cinnamon essential oils were the top promising alternatives than using chemical fungicides to suppress the growth of spoilage fungi. The book provides important and relevant information about herb and spice plants and can be used as a reference material for university students and researchers.