Background: Intra-hospital transportation is the term for when critically ill patients are moved within a hospital for therapeutic or diagnostic reasons. Even for experienced nurses, this kind of work can be risky and very stressful due to the severity of the patients' illnesses and the need for constant monitoring during the transfer. The aim of the study was to evaluate the effect of intra- hospital safe transportation guidelines for critically ill patients on nurses' performance and patients' clinical outcomes. Setting: This study was conducted at Surgical Intensive Care Units in Minia university Hospital, Egypt. Method: A quasi-experimental design was utilized in this study. Sample of the study consisted of all available nurses (70) who are working in the Surgical ICU and convenience sampling of 60 critically ill patients, which divided equal into 30 patients of both study and control groups. Tools: Three tools were used to collect data, Tool (1) Nurses' self-administered questionnaire, Tool (II) Nurses' practice observational checklist and Tool (III) Patients' clinical outcomes. Results: It was observed that great majority (90%) of the studied nurses reported low level of total knowledge pre-implementation of guidelines compared with the majority (82.9%) of them reported high level of knowledge post implementation of guidelines. Additionally, the majority of the studied nurses (90%) had incompetence practice level compared with great majority (98%) of them had competence level of practice post implementation of guidelines and there was high statistical improvement on critically ill patients' clinical outcomes during intra-hospital transportation. Conclusion: A well designed safe intra-hospital transportation guidelines could positively affect the nurses' knowledge and practice and decline the patients' adverse events and complication during transportation. Recommendation: It was recommended that continuous application of intra-hospital transportation guidelines, protocols and checklists in all intensive care units to prevent occurrence of adverse events.