The industrial extraction and purification of steviol glycoside produce huge impure steviol glycosides mixture, commonly knowing as the mother liquor sugar that contains remarkable rebaudioside A (RA, the main steviol glycoside), which is hard to harvest through regular separation. This study presents a strategy to further elevate the harvest of rebaudioside A and to raise the add value of the mother liquor sugar, by raising the recovery rate of RA with enzymatic producing rubusoside directly from the Stevia rebaudiana Bertoni leaves, and obtaining monoglucosyl RA from mother liquor sugar. The produced rubusoside is an edible biosurfactant with superior solubilization ability to drugs, mainly existed in sweet tree plant (Rubus suavissimus S. Lee). Herein, the extraction from Stevia rebaudiana Bertoni leaves in the presence of the β-glucosidase was conducted. The reaction coupling extraction simultaneously produced rubusoside and recovered other steviol glycosides, in which the recovery rate of RA was significantly increased to 184.59% of that obtained from extraction without enzyme. No eutectic crystallization obviously happened during the recrystallization of the reaction-coupling-extracted steviol glycosides. The monoglucosyl RA was obtained from pure steviol glycosides and the extract excluded polyphenols and proteins, instead of producing in the reaction coupling extraction. Moreover, although the mother liquor sugar contains many impurities (total steviol glycosides of 71.8%), the β-glucosidase still can result the production of Ru and monoglucosyl RA simultaneously. The underneath mechanisms and issues in this reaction coupling extraction were investigated in detail.