In this book, we investigated the long-term trend for some of climatic parameters (temperature and precipitation) at 29 stations in Sudan with a minimum record of 29 years. Results showed that there was a positive trend at all stations for mean temperature, while the negative trends for precipitation were computed at all stations.Trends of mean annual temperature were positive at all study stations from 1951-2004, and trends of mean annual temperature were positive at all stations from 1951-1975, while strongly positive trends were computed at all study stations from 1976-2004 corresponding with the global warming trend. Positive trends of mean minimum temperatures were observed at all reference stations from 1951-2004 and 1976-2004. For mean maximum temperature, positive trends were shown from 1951-2004 and from 1976-2004 at most stations, while most trends were positive from 1951-1975. The trends at minimum temperatures are similar to maximum temperatures at most stations. In respect of seasonal temperature, the warming occurred at all seasons in all study periods.