This book is intended for use as reference literature suitable for scientists, teachers, students, and others who are interested in leaf sweeteners that are currently employed in food and beverage industries. All chapters in this book have been written by scientists from related disciplines with a wide range of backgrounds. It is considered that the widest possible interaction of viewpoints and expertise is necessary for transcending the present state of leaf sweeteners as expeditiously as possible. Some overlaps of information in some chapters provided by different authors are allowed in this book, the purpose of which is to prove the precision of viewpoints or results of each other. It is believed that a human being is normally born to like sweets. Unfortunately, traditional calorie-containing sugars are unhealthy because they may cause obesity, diabetes and dental caries. For this reason, there is a great increase in the demand for new alternative "low calorie" or "non-calorie" sweeteners for dietetic and diabetic needs worldwide. This book has collected information about sweeteners from the leaves of Stevia rebaudiana Bertoni, Rubus suavissimus S. Lee and Lithocarpus polystachyus Rehd. The sweet components in the leaves of Stevia rebaudiana Bertoni are proven mainly to be steviol glycosides (including steviosides and rebaudiosides). The sweet components in the leaves of Rubus suavissimus S. Lee are rubusosides. The sweet components in the leaves of Lithocarpus polystachyus Rehd are dihydrochalcone glycosides.