Part-time farm households have shown a rapid increase in number recently in the vicinity of Tokyo. High percentages of part-time farm households to total farm households in “Nogya Shuraku (a kind of rural community)” are found in narrow belts surrounding built-up areas of Tokyo, in patches centered around railway stations and in a relatively large area west of Tokyo somewhat apart from it. A zone of suburban farming where full-timefarm households are relatively dominant surrounds the built-up areas of Tokyo. What are the main factors of such a distribution of the high percentage of part-time farm households? Changes of farm lands to urban uses and a rapid reduction of agricultural land per farm in these areas are the main factors. In the narrow belts surrounding around the built-up areas of Tokyo, the built-up areas are expanding over them. In patches, centered around railway stations, dormitory towns of Tokyo are developing. In a large area west of Tokyo somewhat apart from it, U. S. Army bases, factories, public establshments, schools and collegs, institutions, play grounds, parks, etc. have changed much land for their sites. Farmers are forced to seek for jobs off the farm. Suburban farming is rather more profitable than Japanese agriculture as a whole, but it is less profitable than urban industries near it. However, suburban farmers do not like to change their jobs. It is not only because of shortage in jobs but also because farmers have so little experience and technical training that they can not suceed in the urb an industries. Therefore, they usually do not like to work off the farm except when they are forced by the reduction of farm lands. Rather, they intensify their farming as much as possible in areas where changes of farm lands to urban uses are small.