There are few works performed on the application and analysis of the Fork/Join framework at present. This paper refactored several benchmarks, including series, crypt, sparsematmult and sor, in the Java Grande Forum (JGF) benchmark suite by using Fork/Join framework. Taking the series benchmark as an example, detailed refactoring process was presented. In the experimentation, the execution time of each benchmark was evaluated with different threshold, and the execution time of Fork/Join framework was compared with that of multi-threaded version. Furthermore, the number of work-stealing operations was presented. The experimental results show that the execution time using Fork/Join framework can reduce 14.2% on average than that using multi-thread. When evaluating the series benchmark with data size sizeC and two threads, the execution time of Fork/Join framework is 40% lower than that with multi-thread. Programs using the Fork/Join framework can get better performance than that using multi-thread.