According to the principle of muscular hydrostats, a flexible biomimetic octopus arm is put forward firstly. The method of vector control for the flexible biomimetic octopus arm is presented and analysed in detail. Based on the combination of ARM (advanced RISC microprocessor) and FPGA (Field Programmable Gate Arry), a control system for the flexibie biomiometic octopus arm is discussed, and the functions of every components is analysed. To verify the feasibility and reliability of the method of vector control, experimets are carried out. The experimemtal results demonstrate that this method applied in the control of the biomimetic octopus arm has a good performance.