The purpose of this study was to study the relationship between the prevalence of constipation and beverage intake. Research data were collected from first and second grade female students at Hyehwa High School in Seoul by means of questionnaires. A total of 190 questionnaires were analyzed using the SPSS/WIN program. The results are summarized as follows: The average body mass index (BMI) was 20.7. Of the students, 38.4% had a BMI of less than 20(underweight), and 15.8% had a BMI of over 23 (overweight). However, 84.7% of the students wanted to lose weight. To estimate the prevalence of constipation, five factors were used: frequency and regularity of defecation, time spent defecating, defecation difficulty, and feeling of residue after defecation. The percentage of the students who emptied their bowels every day was 22.1%. About 2/5 of the students (42.1%) had irregular defecation, and 15.2% spent more than 10 minutes in the rest room when defecating. The students who did not have difficulty defecating and those who did not have feelings of residue after defecating were only 24.7% and 28.9%, respectively. The amount of beverage intake per day was 1,062$mell$ 674$mell$ of water, 128$mell$ of milk, 88$mell$ of soft drinks, and 53$mell$ of fruit juice. The amount of beverage intake before breakfast, during breakfast, before lunch and during lunch was about 100 $mell$, each; before dinner, during dinner, and after dinner it was about 200$mell$, each. The amount of beverage intake during the weekend was 120$mell$ greater than on weekdays. Students who drank more beverages, especially water, before breakfast, showed a higher defecation frequency, more regular defecation, spent less time defecating, had less difficulty defecating, and had less feeling of residue after defecation, so that they have a better defecation pattern. Based on these results, increasing the amount of beverage consumption, especially of water, and drinking greater quantities of beverage before breakfast are ways to reduce constipation.