This report extensively summarized a series of researches on the properties, especially flow behavior, of high polymeric materials concerning the polymer processing made by the author of this paper and his co‐workers. Since the high polymeric materials are in most cases viscoelastic, they show a lot of peculiar and diverse flow behaviors. In this paper, various types of the peculiarities and problems in the flow behavior of the polymer melts, such as melt viscosity characteristics, melt fracture, andp‐v‐Tcharacteristics are discussed. Flow characteristics has long been known to be one of the most fundamental properties governing the polymer processing operation. In recent years, many researchers found the great importance of the pressure effect on the melt flow properties and cooling effect on the mechanical properties of the products. As a result, it will be one of the research trend to study thep‐v‐Tstate characteristics of the high polymer, which would give a clear explanation to the above mentioned effects. The matter the author wishes to emphasize throughout this paper is that the rheology has a close relationship with polymer processing and many problems in the polymer processing can be solved through detailed rheological investigations. Thus the author and his co‐workers will find it a great pleasure if their researches on polymer processing will be helpful in the progress of polymer technology. Finally, the author is deeply indebted to many distinguished researchers and outstanding scientists for promotion of the researches mentioned above.