Antibiotic resistance is a global threat to public health, causing continual anxiety of almost intractable bacterial diseases. It is critical to investigate new antibiotic-free strategies to combat bacterial infections like “Klebsiella pneumonia". As a result, the phytochemicals produced by the plant as natural products with antimicrobial capabilities have gotten a lot of interest in the pharmaceutical sciences. Three different plant materials (hot green pepper, potato peel, and ammi visnaga) were collected and extracted by different solvents and screened as antibacterial activity against ten bacterial isolates (S1 to S10). These isolates were identified with Cultural, morphological and biochemical characteristics, then by GNB card and VITEK 2 system. These isolates were identified as Acintobacter baumannii, Klebsilia pneumoniae, Proteus mirabilis and pseudomonas aeruginosa. The hot green Pepper has a strong antibacterial activity against Klebsiella pneumoniae (S3) strain with a minimum inhibition concentration (MIC) of 12 mg/ml and minimum bactericidal concentration (MBC) of 18 mg/ml. The total phenolic content of ethanolic extract of hot green pepper was determined as 8.4±0.9 mg/g. Capsaicin and its derivatives were determined by High-performance liquid chromatography (HPLC) from ethanolic extracts of spicy green pepper. Capsaicin concentration measured 0.66 mg/g, and DihydroCapsaicin measured 0.48 mg/g but Nor DihydroCapsaicin measured 0.10 mg/g.