Recent reports from various countries have indicated that metal accessories may contain high levels of harmful elements. Although this is primarily a concern because of the risk of accidental swallowing by infants and young children, information on this issue in Japan remains limited. Therefore, this study aimed to investigate the contents of eight harmful elements (Sb, As, Ba, Cd, Cr, Pb, Hg, and Se) in 47 metal accessories available in Japan that infants and young children might accidentally swallow, and determine the migration of these elements from the accessories. Pb (80–2,600 mg/kg) and Cd (50–660,000 mg/kg) were detected in metal accessories, with some products exceeding the European Union regulatory limits for jewelry articles (Pb: 500 mg/kg; Cd: 100 mg/kg). Cd migration was detected from eight metal accessories with concentrations ranging from 0.99 to 1,100 mg/kg. Two products exceeded the maximum acceptable migration limit of 75 mg/kg specified in ISO 8124-3:2020 “Safety of toys-Part 3: Migration of certain elements.” In contrast, Pb migration was detected in only one product and was less than 10% of the maximum acceptable migration limit. Notably, two products exhibited high Cd migration (390 and 1,100 mg/kg), whereas some products contained high levels of Pb (up to 2,600 mg/kg) and Cd (up to 660,000 mg/kg). These findings highlight the need for continued monitoring of harmful element content and migration from metal accessories, considering not only accidental swallowing but also other exposure routes, such as mouthing behavior.