Infiltration and Extravasation injury resulting from administration of intravenous therapies via peripheral intravenous catheters or central venous catheters, newborns and children are more exposed to infiltration and extravasation injuries. Aims: Evaluate the effect of evidence based guideline for prevention and management of infiltration and extravasation on neonatal nurses Adherence. Evaluate the effect of implementing evidence based guideline on the incidence rate of intravenous infiltration and extravasation among studied neonate . Setting, The study was conducted at (neonatal intensive care units) at Shebin EL Kom teaching hospital and Tala central hospital at Menoufia Governorate. Sample: Convenience sample of 30 nurses and Purposive sample of 30 neonates were obtained from the previously mentioned neonatal intensive care units. Tools , four tools were used for data collection tool one: Structured Interview Questionnaire. was utilized to identify nurses' knowledge about intravenous infiltration and extravasation, tool two was an clinical practices guideline adherence scale to assess nurses practices about prevention and management intravenous infiltration and extravasation, tool three include the intravenous infiltration assessment scale, tool four include extravasation assessment scale. The results of this study showed, the highest percentage of nurses had significantly high knowledge and practices regarding adherence to evidence base guideline of prevention and management of intravenous infiltration and extravasation on posttest than pre test ,in addition, marked decrease in the incidence rate of Infiltration and extravasation between neonates on the posttest than pretest with no statistical significant differences . Conclusions implementation of evidence-based clinical practices guideline regarding prevention and management of intravenous infiltration and extravasation significantly increases nurses' knowledge and practices regarding adherence to evidence base guideline, Also, it decreased the incidence rate of intravenous infiltration and extravasation among studied neonate. Recommendation: continuous training of evidence based clinical practices guideline should be established in each neonatal unite to enhance nurses' adherence regarding intravenous infiltration and extravasation prevention and management.