The seed germination characteristics of Capsicum frutescens from the Ryukyu Islands were studied. Constant temperatures and darkness conditions inhibited seed germination in Ryukyu Islands' C. frutescens, whereas fluctuating temperatures and light irradiation accelerated germination, suggesting the presence of dormancy in these seeds. This dormancy was considered to be weak because the seeds could germinate at constant temperatures and under continuous darkness. Therefore, C. frutescens from the Ryukyu Islands could be at an intermediate stage between wild and domesticated forms. Since it was revealed that the seeds of C. frutescens from the Ryukyu Islands displayed dormancy, seed dormancy of C. frutescens obtained from Southeast Asia was studied. Among 72 accessions, 47 failed to show dormancy and germinated very rapidly; in these accessions, plant organs were larger than those in other Southeast Asian accessions. On the other hand, the seeds of the other 25 accessions from Southeast Asia showed a weedier character, including some dormancy and smaller plant organs. Accessions of C. frutescens from Southeast Asia thus appeared to be at various stages of domestication, suggesting that the domestication process had already stabilized under low selection pressure and the tropical climatic conditions of Southeast Asia. The various accessions of C. frutescens in Southeast Asia ranging from fully domesticated to weedier forms are very useful for breeding and horticulture as genetic resources.