Takahashi Ryoji was born into the family of the Edo metalworker Shin'un-sai Toshitsugu, inheriting a lineage already established in the craft of sword-fitting production. He first studied metalworking under his father and under Shibahara Juro before becoming a disciple of the celebrated Bakumatsu master Toryusai Seiju (Tanaka Seiju), one of the foremost figures of the late Edo period. Among Ryoji's own pupils was Okada Setsuga, ensuring the continuation of the lineage into the Meiji era. A distinct figure within the same family line was Takahashi Yoshitsugu, born in Tempo 13 (1842), who likewise studied under Toshiyoshi and Tanaka Seiju but died in Meiji 6 (1873) at the young age of thirty-two, leaving behind a small but remarkably accomplished body of work.

Ryoji is recognized by the NBTHK above all for his mastery of fully unified fittings suites -- issaku kanagu -- executed entirely in solid gold (kin-muku). His decorative programs deploy an elevated iconographic vocabulary: the "Four Gentlemen" (shikunshi), the "Three Friends of Winter" (saikan sanyu), and chrysanthemum-spray (eda-giku) compositions recur across his oeuvre. His technique encompasses takabori with iroe, nanako-ji groundwork, suemon applique, katakiribori, kebori, and hira-zogan in gold, silver, shakudo, and shibuichi. The NBTHK consistently notes how his gold fittings achieve effects that are at once "weighty and luxurious" (omoomoshiku kago) and "refined and tasteful" (johin na aji), with the brilliance of solid gold harmonized against restrained lacquer grounds to produce mountings of cohesive elegance.

Within the tradition of Bakumatsu metalwork, Takahashi Ryoji occupies a position of particular distinction as a maker capable of conceiving and executing entire mounting programs as unified artistic statements. The NBTHK characterizes his productions as "opulent and luxurious" and "thoroughly in keeping with refined Edo taste," singling out the coherence of his issaku suites as their defining quality. His daishi koshirae, uchigatana koshirae, and tsukubei mountings represent the culmination of late-Edo metalworking ambition, in which the splendid radiance of gold and the cultivated elegance of the design are, in the words of the designation committee, "fused to striking effect."