Variability and trends of temperatures in the cities of São Paulo State/Brazil. This article analyze the variability and evolution of temperatures in fourteen cities in São Paulo State, Brazil. The maximum and minimum temperature data were obtained by National Institute of Meteorology (INMET) and the University of São Paulo (USP), 1961 to 2011. The methods used are : 1) descriptive statistics techniques to analyze the annual variability (Percentil); 2) Homogeneity tests (Pettitt). Thes results show that there is a significative increasing trend of temperatures in mostof weather stations, caused especially for the evolution of land use, local effects (cities) and global effect. The majority of very cold and cold years are present in the decadal period 1960-1970, and a gradual increase the temperature at 2000s, when the warmest years are observed. The Pettitt test show a positive changes trends in the eleven weather stations , between the years 1983-1993, for the maximum temperature, and also, for the minimum temperatures in dix weather stations.