Introduction: Hospital acquired infection (HAI) is an infection acquired in health care facility by a patient who was admitted for a reason other than that infection, this infection is not present or incubating at admission. HAIs are among the leading causes of death and they cause significant morbidity among patients who receive health care. Objective: To implement an intervention program in the form of training of health care workers in the selected hospitals on infection control standard precautions including the preventive bundles. Methods: This intervention study was carried out over 13 months in 4 MOH hospitals comprising 11 ICUs. All hospitalized ICU patients were followed up starting from the date of their ICU admission till occurrence of one or more HAI. All age groups were included in the study. Case definitions of HAIs included in the study were based on CDC/NHSN Surveillance Case Definitions. The complete medical records for Neonatal ICUs were 482 patients, for medical ICUs were 590 patients and for medical / surgical ICUs were 1088 patients. Results: The overall patient infection rate, overall patient day rate, hospital acquired pneumonia rate, urinary tract infection rate and blood stream infection rate, all declined significantly after the intervention than that before the intervention. Conclusions: Implementation of the intervention in the form of training course to the health care workers on the recommended infection control standard precautions, including the preventive bundles resulted in significant reduction in HAI rates after the intervention than before the intervention.