Objective: This study aimed to determine the efficacy of Telenursing on maternal-infant attachment and stress on preterm infant’s mothers in NICU. Design: This study is a clinical trial that will be conducted in Isfahan. Setting and conduct: In this study, 50 mothers of preterm infants with inclusion criteria admitted in NICU of the Isfahan Shahid Beheshti hospital randomly assigned to an experimental group and a control group. Participants including major eligibility criteria: Gestational Age 33-37 week with no evidence of physical or congenital problem and no Deterioration of their disease. Intervention: In the experimental group within seven days after birth until a week after discharge nursing education with Telenursing will be done by telephone system. This telephone system consist of two parts offline and online. Off line system have 10 codes with recorded information about NICU, characterization of premature newborns, changes of weight, length and head circumstances in premature newborns, therapeutic procedures in premature newborns, equipment in NICU, relaxing premature newborns, different methods of feeding in premature newborns, breast milk storage and handling, ways of increasing milk expression, listening to relaxation voice messages. The offline system will be always available by phone during 24 hours. In online part mothers can contact to the researcher and ask their questions. Control groups received only routine interventions. variables: During seven days after birth both groups will complete Parental Stress Scale: Neonatal Intensive Care Unit (PSS:NICU) and Maternal Postnatal Attachment (MPA) scale, on the day of discharge they will complete PSS:NICU and a week after discharge, they will complete MPA scale.