An anticipative recursively-adjusting co-allocation mechanism (ARAM) includes the steps of: measuring a transmission bandwidth of a candidate server by a bandwidth measurement module; referring to the transmission bandwidth to calculate a recursive parameter value, and calculating a desired allocating file size of present round according to the recursive parameter value and an unassigned file size; allocating the desired allocating file size to the candidate server according to the transmission bandwidth and a transmission completion percentage of the candidate server at a previous round; performing the transmission and calculating the transmission completion percentage of each candidate server; examining the transmission completion percentage of the candidate sever; and examining whether or not an allocation of files is completed if any candidate server has completed a transmission, and looping to the next round if the file allocation has not been completed so as to enhance the data transmission performance effectively.