To summarize and classify the frontal appearance of the philtrum in Nanjing' s young population, so as to assess the role of philtrum in the face aesthetics. From August 2010 to December 2011, 160 Nanjing's youth, aged from 20 to 25 years old, underwent photographic study and measurement. The aesthetic rate was graded both for philtrum and the whole face. The results were statistically analyzed. The standard philtral aesthetic appearance is a slim isosceles trapezoid, with an isosceles triangle whose obtuse angle is about 140 degrees reversed at the bottom, like a necktie. The aesthetic rating was highest for philtrum in male NO. 105 and female NO. 33, while for the whole face in male NO.45 and female NO. 7. The mean data of the major parameters were as follows: the length of mouth width was (50.0 +/- 4. 3) mm (male), (47.0 +/- 4.0) mm (female); the length of right red lip was (20.2 +/- 2.4) mm (male), (19.3 +/- 2.3) mm (female); the length of left red lip was (20.2 +/- 2.2) mm (male), (18.9 +/- 1.8 ) mm (female); the length of right philtrum column was (15.5 +/- 2.0) mm (male), (13.6 +/- 2. 2) mm (female); the length of left philtrum column was (15.6 +/- 1.9) mm (male), (13.7 +/- 2.3) mm (female); the length of philtrum sulcus was (17.3 +/- 2.1) mm (male), (15.3 +/- 2.4) mm (female). The upper breadth of philtrum was (5.6 +/- 0.8) mm (male), (5.5 +/- 1.1) mm (female); the middle breadth was (9. 5 +/- 1.1) mm (male), (8.5 +/- 1.2) mm (female); the lower breadth( cupid bow width) was (13.8 +/- 1.8) mm (male), (11.8 +/- 1.6) mm (female). The right half of cupid bow was (7.5 +/- 0.9) mm (male), (6.5 +/- 0.9) mm (female); The left half of cupid bow was (7.2 +/- 0.9) mm (male), (6.1 +/- 0.8) mm (female). The philtrum angle was (141.2 +/- 8.0) degrees (male), (141.3 +/- 6.1) degrees (female). Although there is slight difference in the measurement results between two sides of philtrum column and cupid bow (P < 0.01), it is not obvious by naked eyes. Except for the upper width of philtrum and the philtrum angle (P > 0.05), the other parameters have significant sexual differences (P < 0.05). The beautiful philtrum can not mainly decide the whole face aesthetics, which usually shows a harmony relationship between all the facial aesthetic units. The measurement results can be used as a reference for philtrum plasty.