Embodiments of the present invention disclose a data processing apparatus and method for processing serial tasks, which can reduce, in a data processing process, a quantity of times of reading an output result from disks of node devices in a distributed system, thereby reducing time required and network resources occupied for processing a large amount of data. The method in the present invention includes: acquiring at least two MapReduce tasks, where the at least two MapReduce tasks are serially arranged according to an execution sequence, and when two MapReduce tasks are serially arranged, an output value obtained after the former MapReduce task is executed is an input value of the latter MapReduce task; combining the at least two MapReduce tasks to obtain a target MapReduce task; and executing the target MapReduce task, and obtaining an output result of the target MapReduce task.