Background: Standards precautions are designed to protect staff from risks resulting from exposure to blood and body fluids and to protect patients from potential cross infection. Knowledge of clinical infection control practices is continually growing and changing. Objectives: the present study was conducted to assess nurses' Knowledge about Infection control standards precautions in primary health care settings. Methods: This study was cross sectional study that was conducted in six primary health care settings (PHC) in Manzala District affiliated to the Ministry of Health and Population. PHC settings were selected by stratified random sample method. Seventy nine nurses were included in the study.  Data were collected by using open ended questions sheet, which was self-administered. Results: The nurses showed a poor level of knowledge regarding most categories of standard precautions. Conclusion and Recommendations: Mandatory regular base educational program must be planned to overcome the weak level of knowledge and improve and update the nursing performance regarding standard precautions.