The most flourishing gold culture of Korean history was at its height in Silla of the Three Kingdoms period ranging from the 5th century to the 6th century. However, it was not flourishing any longer and it went in decline. The purpose of this article is to look at the splendid gold culture from the 5th century to the 6th century and analyze the causes of its decline. The Three Kingdoms period around the 4th~5th centuries was the developing period which had the most outstanding cultural and political activities on the international stage in Korean history. People in the Three Kingdoms period could acquire the foundation of developing ancient Korean metal craft, especially jewelry because they developed the new way of mining gold and silver and metallurgy. It was based on this era to build up the imposing ancient tombs in the Three Kingdoms period, and the knowledge of craft art in the era was mostly gained from their inside ancient tombs. It was the golden jewelry that was the most distinctive thing among craftworks excavated from these ancient tombs in the Silla period. Most of all, the outstanding craftwork is the golden crown excavated in the Gyeongju area. The golden crowns, belts and earrings presented diversity rarely seen in the jewelry world history as well as masterful gold jewelry. There are gold metalwork skills developed from the golden earrings in Silla, which is called “NuGeumSeGong”. It is the same techniques as a fringe and embroidery of the design with gold thread and grain, which is named “Filligree” from ancient Greece in the West. In addition, the development of “Gokok” which had been regarded as the origin from the teeth of some fierce animals also attracts people’s attention as the Silla jewelry. The “Gokok” of Silla made of Jade, crystal•glass, and other jade was used in jewelry such as golden crowns, and it had been spread in Japan. Brilliant golden jewelry of the ancient Silla had been started to decline after the Unified Silla. The Silla culture around A.D. 6 had been declined with the decline of the culture of ancient tombs, but it started to build on Buddihism stone pagodas, whereby the installation work to enshrine small crystals inside of the pagodas had been developed. This is because the cremation culture of Buddihism got spread, and this made big tombs and diverse golden ornament disappeared gradually. However, instead, the golden culture turned over a statue of the Buddha of Buddhist temple and an object of metal craft.