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Background The technology of frozen dough (frozen dough) as a new breakthrough in efforts to improve efficiency and maintain the quality, is widely applied in the food industry to facilitate the production of bread, noodles, and dumplings, and is mainly produced from wheat flour (WF). The WF which is not derived from Indonesia, forced manufacturers to explore new formulations using local material. Purple sweet potato was chosen due to its color as an antioxidant source, potented to be functional food. But purple sweet potato has low binding capacity for bakery ingredients, thus the role of gluten from wheat flour is still needed. Moreover, the addition of yeast and emulsifier to the dough plays a role in maintain the volume when the dough baked, The research was conducted in University of Muhammadiyah Malang along 6 months (September 2018 – February 2019). Aims The aim of this research are to develop formula of frozen dough -substituted by purple sweet potato flour and added between yeast and emulsifier- along storage time and to know its effect toward sweet bread properties. Materials and Methods Firstly, the formula of frozen dough was designed with different of yeast concentrations in 3 levels (3%; 5%; 7% w/w) and types of emulsifiers (eggs, Lecithin, SP), while purple sweet potato flours substituted is 20%. The dough was mixed using straight dough method and stored in freezer at -20oC for three days and then frozen dough was baked to obtain sweet bread. According to Standard of Sweet Bread in Indonesia Number 01-3840-1995, the sweet bread was analyzed by its moisture, ash, and sensory test (taste, aroma, and color). Moreover, antioxidant activity, redness and volume expansion capacity were tested. Data were analyzed by ANOVA and least significant difference (LSD) test at level of 0.05 using Microsoft Excel. Results Based on Table 1, when compared between sweet bread obtained from fresh dough and frozen dough on the first day of storage, it showed that 8 out of 9 formulas did not effect on the volume expansion capacity of sweet bread significantly, while when compared between volume expansion capacity of sweet bread obtained from frozen dough on 1st and 2nd day of storage, only 1 formula showed a significant difference. Whereas only 2 formulas had a significant difference when compared between the volume expansion capacity of sweet bread produced from frozen dough on the 2nd and 3rd day of storage. This phenomenon exhibited that the freezing of dough did not greatly affect the volume expansion capacity of the sweet bread. Frozen dough with a straight dough mixing method, a short fermentation time allows no loss of viability and gas capability during the frozen storage which is quite significant (Tressler et al, 1968). In addition, the formulations carried out cause the average development of sweet bread reaches above 50%. This indicates the role of the emulsifier in the development of the bread. Emulsifiers will impro