It is a fact that there are recent increasing trends or incidence of the colorectal carcinoma among other colorectal diseases. In such trend, the early detection remain to be most important by the air contrast barium enema and total colonofiberscopy. There are several ways to prepare the colon for barium enema and colonofiberscopy which include several agents. The mechanical cleansing have been used most frequently since Brown's method was adapted to be most perfect for colon deansing. The ideal laxatives and enema solutions were limited to adequate dose, it's effectiveness, patient's diet and bowel habit, minimal side effect, low cost and simple to perform. In order to compare the effectiveness of various cleansing solutions, six experimental methods were formed as shown; 1. normal saline enema, 2. castor oil with normal saline enema, 3. castor oil with soap suds enema, 4. magnesium citrate with normal saline, 5. magnesium citrate with soap suds enema and 6. ingestion of Golyetly solution. The authors have compared and determined the degree of cleanness by an experienced endoscopist. The total number of patients was 247, age distribution was $43{\pm}15$ years old, and sex distribution was 133 males and 114 females. The grade I and II represented no difficulties at performing the colonofiberscopy, but grade ill and N had some difficulties, even unable to perform the colonofiberscopy. The effectiveness the cleansing agents, represented with grade I and II was 95.9% (47/49) in method 6, 93.2%(54/58) in method 2, 83.3%(30/33) in method 3, 70.0%(28/10) in method 5, 66.7%(16/24) in method i, and 45.7%(18/40) in method 4. Method 2 and 6 were the most effective in normal bowel habit patients. In constipated patients, method 6 was the most effective and all method except method 11 were effective in diarrhea patients. The degrees of less mucosal irritation by various bowel cleansing method were in the order of method 6(100%), 1(100%), 5(74%), 2(69%). In subjective symptoms and cleansing groups, abdominal distension, pain, nausea and vomiting were complained, and that's subject symptoms were in the order of method 3(88.9%), 6 (79.6%), 1(75%), 5(72.5%), 2(72.4%), 4(67.5%). In conclusion, we believe that the Golytely of the mechanical cleansing solution for colonofiberscopy was the most effective, but others depended on the patient's condition und bowel habit.