The aim of this study was to find out the vertical distance between the most antero-superior point on the lingual frenum and mesio-incisal edges of mandibular central incisors in dentulous subjects belonging to different age groups.we took 120 dentulous subjects (60 men, 60 women)and 20 complete denture wearers.Depending upon the age, the dentulous subjects were divided into three groups. Each group consisted of 40 subjects (20 men, 20 women).mandibular casts were made from irreversible hydrocolloid impression material in stock trays for each subject. All subjects were instructed to elevate the tongue while the impressions were made. The vertical distance between the anterior attachment of the lingual frenum and incisal edges of mandibular central incisors was measured on the casts. Means and standard deviations of the measurements were calculated and statistically analyzed. Overall (irrespective of gender) normative range for vertical distance between the anterior attachment of the lingual frenum and mesioincisal edge of mandibular central incisor among north Indian dentulous subjects is 9.52-10.24 mm.if we consider gender it is 10.00-11.13 mm for male and 8.82-9.58 mm for female.