It is well documented that fine root production (FRP) in forest ecosystems is large due to rapid turnover in spite of the small standing crop. Several methods have been applied to measure FRP: sequential coring, ingrowth core, nitrogen budget, soil carbon budget, and minirhizotron methods. The processes as well as advantages and disadvantages of each method were briefly reviewed in this report. The soil micromorphological method applied in a Japanese coniferous forest was described. This method enables to determine the fine root distribution and microstructure of the organic layer where fine roots are mostly concentrated. The ability to observe root cross-sections may improve the classification of the physiological status of the roots. The data obtained by this method at one time indicated that those fine and active roots were distributed mostly in the superficial litter layer of the soil. In the fermentation layer below, a smaller number of active types of roots were found. Periodical collections of samples may enable to study seasonal changes of fine roots and supply additional information on root ecology. The most difficult problem in the study of fine root dynamics is still the methodology. Over- and underestimation should be corrected to acquire more accurate information on forest production ecology and the role of forests in carbon and nutrient balance.