本檔案收藏了余仁生的商務資料。余仁生是一家傳統中藥行，在 19 世紀開業之初只是一小型中藥雜貨店，直到 20 世紀由創辦人的獨子余東旋接手以後，才發展成業內知名的品牌。資料主要是文檔，包括帳簿、銀行結餘對數單、進支結算簿、會計師報告、資產損益表、匯單簿、支款及轉賬單、來往數簿、法律文件、稅項及各類繳費收據、信件、會議紀錄等，涵蓋1915 年至1969 年，而以1940 年代至1960 年代的數量最多。材料按文件類型分為4個系列，再依年份順序排列。

The Eu Yan Sang Collection contains the business materials of Eu Yan Sang (余仁生), a traditional Chinese medicine firm first ran as a small shop in the 19th century and became a renowned brand name in the industry in the 20th since taken over by Eu Tong Sen (余東旋), its founder’s only son.　Materials, mainly textual, comprise account books, bank statements, incomes and expenses record, auditor’s reports, profit and loss accounts, remittance books, payment vouchers, trading record, legal papers, tax and various payment receipts, correspondence, letters, meeting minutes etc. covering a period from 1915 till 1969 (bulk in 1940s-1960s). Materials are currently arranged into 4 series according to document type and further arranged chronologically.