An ananysis on the chronological development of planning and technologies relating world lock canal from medieval times up to the age of Panama Canal was executed.
　The conclusions were:
1. The features of the lock canal around the world did not basically change until the end of the 18th Century. At the beginning of the 19th Century, devices to overcome large waterhead were established and incremental development of lock canal started. In Japan and China, inland navigation has been developed from ancient age, however, unlike Europe, lock canal could not emerge due to various reasons.
2. Since in the 1880's new technologies such as steel gate, concrete lock, dynamite and dredger they would have been able to construct a small canal in Panama in the era of de Lesseps.
3. Among outstanding technologies in the 19th Century, gravity concretre structures with steel gates to withstand large water pressure was a key technology. The prototype of the present Panama Canal locks was the first massconcrete structure.
4. By explaining the trend of incremental excavated volume relating to the past Panama canal plans, an approproate plan was drafted for the future.