Background: Expectoration of blood that originated in the lungs or bronchial tubes is a frightening symptom for patients and often is a manifestation of significant and possibly dangerous underlying disease. Tuberculosis was and still one of the common causes followed by bronchiactasis , bronchitis, and lung cancer. Objectives: The aim of this study is to find the frequency of causes of respiratory tract bleeding in 100 patients attending alkindy teaching hospital.Type of the study: : Prospective descriptive observational study Methods of a group of patients consist of one hundred consecutive adult patients, with Lower respiratory tract bleeding are studied. History, physical examination, and a group of selected investigations performed, including complete blood examination and blood film, PT, PTT, sputum direct gram and AFB stain, cytology ,chest radiography, CT scan, and bronchoscopy when indicated.Results: pulmonary tuberculosis, acute bronchitis, lung carcinoma, and bronchectiasis are the major causes of hemoptysis in our study with 27%, 23%, 23%, 20% respectively. Of the included patients 63% were males, specially age 41-60, while 37% were females. The primary malignancy is more common than secondary cancer, and that squamous cell carcinoma, and adenocarcioma, are the most common.Conclusions: Tuberculosis is the main cause of lower respiratory tract bleeding, followed by lung carcinoma bronchitis, and bronchiactesis. Most of the patients are males and in middle age , sever bleeding is not common and squamous cell carcinoma is commonest cause regarding malignancies followed by adeno carcinoma
