Maternal weight gain determines maternal and fetal outcome. Lower weight gain is associated with low birth waight of fetus and pre term delivery while higher weight gain is associated with gastational diabetes mellitus higher birth weight and complication related to it. Maternal weight gain itself depends on nutritional intake and also various medical condition like diabetes mellitus, hypertantion. The institute of medicine guideline says that required gastational weight gain depends on pre gastational BMI, and it needs to be tailored indivisualy. We have done prospective observational study at Kamla Raje hospital Gwalior from january 2019 to june 2020, in which we studied on 500 women maternal weight gain , factors affecting it and maternal outcome. We found 41% underweight while only 4.2% women were overweight. Maximum women were from 20-29 age group(69.8%) and they commonly gain inadequate weight (71%). 53% of women were rural and 47% were urban. 65% of women who gained inadequately weight were rural while 60% of higher weight gained women are urban. women with adequate weight gain were associated with adequate weight gain (83%). most common maternal outcome in inadequate weight gain women was PROM(25%) while in higher weight gain women developed hypertention commonly (38%). 71% of inadequately weight gained women delivered by normal vaginal delivery and 78% of higher weight gained women needed cesarian section. We found that women with inadequate or higher waight gain as per IOM guideline associated with poor maternal outcome. Preconceptional counciling regarding nutrition according to BMI and physical activity to be done and also gastational waight gain according indivisual BMI should be advised.