This paper evaluated the influence of temperature and concentration of the sucrose syrup on the pre-osmotic dehydration of peaches. Physical (colour and texture) and chemical variables (soluble solid content; total sugar, reducing and non-reducing sugar contents; and titratable acidity) were investigated, as well as the osmotic dehydration parameters (loss of weight and water; solids incorporation). An experimental central composite design was employed varying the temperature (from 30 to 50 °C) and concentration (from 45 to 65 °Brix) and maintaining the syrup to fruit ratio (4:1), process time (4 hours), and format (slices). The degree of acceptance was used in the sensory analysis evaluating the following characteristics: appearance, taste, texture, colour, and overall quality using a hedonic scale. The results were modelled using the Statistica program (v. 6.0) and the Response Surface Methodology. The mathematical models of the following dimensionless variations yielded significant (p < 0.05) and predictive results: soluble solids content, total and non-reducing sugar contents, titratable acidity, colour parameter L*, and water loss. The models of the attributes colour and appearance yielded significant (p < 0.10) but not predictive results. Temperature was the prevalent effect in the models. The process conditions in the range from 50 to 54.1 °C and from 45 to 65 °Brix led to greater water losses and better sensory performances.304940948Abugoch, J.L., Guarda, M.A., Estudo de la perdida de acido ascórbico total em rodajas de kiwi, durante la deshidratacion osmótica (1991) Alimentos, 16 (5), pp. 15-19Araujo, E.A., Estudo Do Processo De Desidratação Osmótica E Secagem De Nectarina (Prunus Persica), p. 2005. , 113 f. 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