The semen is a mixture of spermatozoa and seminal fluid. The seminal fluid is a composite mixture of secretions from the various accessory sex glands in the seminal tract. The fertilizing capacity of the human spermatozoa cannot be assessed directly. So the fertility-potential in men must be determined by the indirect means, semen analysis. Some routine chemical analysis of the seminal fluid is suitable for evaluation of the secretory functions of the accessory sex glands. But there are many pitfalls for those who forget the special features of the seminal fluid. The semen analysis is commonly regarded the most valuable diagnostic procedure in the evalution of the male fertility. Through this procedure we can get the valuable informations on the testicular production of spermatozoa, the morphology and functions of these cells, and secretory functions of seminal tract. But this analysis has been overestimated for a long time when it is allowed to replace a proper clinical test of the men, and it has been used simply to classify the men as fertile, infertile or sterile. On the other hand, the clinical and scientific values of seminal fluid and semen analysis for other andrological problems are overlooked or underestimated. In the method of semen analysis, there have been many variations in procedure for collection, processing and description of specimens. And the interpretations of semen analysis and examination of seminal fluid are confused and somewhat subjective. So it has been very difficult that a certain result of scientitic advances in research or clinical practice for the human semen in one laboratory are repeated and confirmed by others. And in the seminal fluid and semen analysis, there have been many problems in relevance, precision, accuracy and interpretation. Also there are many mistakes in using or the terminology related to the investigation of infertile men and semen analysis. So there have been many demands for the standardization of semen analysis. In 1977, WHO provided the standard manual for the management of human semen. These discussions will be focused on the problems of seminal fluid and semen analysis with particular reference to the factors related to the common mistakes and misleads, and will introduce some improvements of technical field in examination of human semen. The following subjects will be discussed; 1. General reexamination for routine semen analysis 2. Technical reexamination for routine semen analysis 3. Reexamination for the evaluation of biochemical analysis of seminal fluid.