Nyctanthes arbour-tristis belongs to the Oleaceae family and is known as Harsingar. Harsingar is an important Indian medicinal plant; traditionally, harsingar is used to treat skin diseases including piles and scalp itching infections, and used as a laxative, diaphoretic, and in chronic fever. N. arbour-tristis microscopic and powder microscopy revealed the presence of stomates, gland cells, vein islet, and trichome. Carbohydrates, amino acids, steroids, coumarin glycoside, flavonoids, alkaloids, and tannins were discovered in preliminary phytochemical analysis. All of the studies were carried out in accordance with WHO guidelines. Quantitative analysis of N. arbour-tristis was done through total phenolic content, total flavonoid content, and total tannin content. Leaves of N. arbortristis were screened for antimicrobial potential against S. typhi, S. aureus, B. subtilis, E. coli by using the MIC method, and chloramphenicol was taken as standard. Among all extract, N. arbour-tristis chloroform extract shows maximum antimicrobial potential.