Introduction: Placenta is essential for normal fetal development. Failure of the placenta can result in many fetal conditions. Placental development and function can be assessed by a number of methods, including measurement of placental weight. Objective: The aim of this study was to evaluate survey of placental weight and associated factors. Materials and Methods: In this study pregnant, women with singleton pregnancy and gestational age between 37-42 weeks delivered following complicated or no complicated pregnancies were included in a cross-sectional study. Also the patients were categorized into high placental weight (>750 gr), normal placental weight (330-750gr) and low placental weight (<330 gr). The placental weight, birth weight, maternal age, gestational age, parity, preeclampsia, history of maternal diabetes, route of delivery, infants gender and Apgar score were recorded and analyzed with chi2 test.Results: 1088 patients were included in this study. The mean maternal age was 25.35±5.6 and gestational age at delivery was 274.51±9.56 days. The mean weight of birth and placental weight were 3214.28±529, 529.72±113 respectively. The prevalence rates of low and high placental weight were 2% and 2.8% respectively. There were statistically significant relationships between placental weight and birth weight, fetal distress, Apgar score, maternal diabetes, preeclampsia and kind of delivery. (P<0/05) Conclusion: In this study, it was seen that placental weight can be related to some important variables that influence some maternal and neonatal outcomes. Therefore, attention to placenta and its growth during pregnancy, for example by sonography can guide us in providing neonatal health and even can be the base of preventive medicine. It appears that placental weight lower than 330gr can be a warning.