In Portugal, the noise is regulated by the Regulamento Geral do Ruído (RGR). This statute introduces, like its precursor, the consideration of the variable based on sound urban planning. In this context, the implementation of policy planning and urban design should ensure the quality of the sound environment, promoting the proper distribution of functions of housing, work and leisure. Viana do Castelo is a city in northern Portugal with an area of 37km ² and a population of approximately 36,500 inhabitants. The urban center comprises two parishes, Monserrate e Santa Maria Maior. We will try it to meet the most critical areas in terms of noise so as to reduce it to below the legal limit according to the legislation. The noise reduction measures to propose a hierarchical respect, namely, to give first priority to action at source, followed by measures of activity in the propagation and as a last resort to action in the receiver. Using the noise shaping will calculate various scenarios, to assess what are the best options to take in different areas of the study area. This article has as its main objective the implementation of a low velocity zone in the historic city of Viana do Castelo, intending to find measures and solutions to eliminate or mitigate noise in areas of conflict acoustic, making use of a prediction model noise in an environment of Geographic Information Systems.