A beam-forming device includes a first target sound blocker 103 and a second target sound blocker 104 that remove a target signal having a correlation mutually from a first sound signal x1 and a second sound signal x2 which are converted by first and second microphones 101 and 102, a phase synchronizer 105 that synchronizes the phases of the first sound signal x1 and the second sound signal x2 and synthesizes these sound signals by using information acquired when the first target sound blocker 103 removes the target signal, and a noise learner 106 that learns a noise component included in an output signal of the phase synchronizer 105 from signals from which the target signal is removed by the first target sound blocker 103 and the second target sound blocker 104.