This paper evaluates long-term trends of wage differences among Brazil's rural workers. The later are divided into two groups, permanent and temporary workers. Johansen's co-integration methodology and 1966 through 2002 data set, organized by semester averages, are used in this paper. There are two major conclusions. First, there is no co-integration among Brazilian permanent workers' wages when Brazil's regions are compared; however, there is high co-integration among permanent workers' wages inside each region. Permanent workers' wage differences were large until the late of 1980s, reducing significantly during the 1990s. Second, there is high co-integration among Northeastern temporary workers' wages and other regional wages. It implies that Northeastern workers arbitrate temporary workers' wages in other regions. It happens because there is large mobility of temporary labor from Northeast to other regions. Temporary workers' wages at Center-West, South and Southeast have co-integration, probably, because Northeastern workers arbitrate their temporary workers' wages. In spite of these co-integration relations among temporary workers' wages, there is large difference among them. Northeastern workers' wages are below the wages paid in other regions.