For robust quantum computation, a quantum operation applied to a qubit system must be as close as possible to a desired unitary operation. It is necessary to estimate an experimental quantum process and compare it to an ideal unitary operation quantitatively. The estimation of a quantum process requires the tomographic reconstruction of the output states for all possible input states, the number of which exponentially increases with the number of qubits. A quantum process tomography was experimentally realized in NMR by obtaining output states sequentially for all possible input states. This method suffers from exponentially increasing experiment time with increasing number of qubits and it is suggested that all possible input states are superposed in only a single entangled state. Then the tomography of quantum process can be obtained in one experiment by the quantum parallelism of entanglement. In this thesis, a process tomography has been realized in NMR by using this quantum parallelism and an experimental result for the single qubit gates is presented.
