The ultrashort laser excitation of nonmagnetic/ferromagnetic/nonmagnetic (NM/FM/NM) heterostructures is intensively studied as a terahertz (THz) emitter. Herein, the combined spintronic and photonic ultrathin metal heterostructures are exploited to realize actively modulated THz radiation. It is demonstrated that the THz radiation can be mediated coherently through the charge current induced by the inverse spin Hall effect (ISHE) and the built‐in transient current quasi‐simultaneously created within the striped NM/FM/NM heterostructures. The waveforms of THz radiation can be shaped by the charge current confinement effect, including the amplitude modulation and the center‐frequency shift. These findings can be utilized for device‐oriented opto‐spintronics and also extend the established THz emitter to THz modulator.