A Joint Beam Commissioning Performed at CSNS Date: 2017-11-04 Author: The joint beam commissioning among accelerators, target station and instruments started in the China Spallation Neutron Source (CSNS) on November 1, 2017. At about 15:00 p.m., the proton beam pulses with repetition rate of 1Hz at an average beam power of 300~400W from accelerator collided on the tungsten target. All systems of the target station were operating smoothly. Continuous cold and thermal neutron pulse from three types of moderator were output for neutron instruments, while the target imaging system successfully captured the proton beam imaging on the target. Up until 21:00 p.m., detectors of all three Phase-I instruments, including the General-Purpose Powder Diffractometer (GPPD), the Small-Angle Neutron Scattering instrument (SANS) and the Multi-purpose Reflectometer (MR), measured the neutron signals. Raw Diffraction Data of a Standard Sample Si from GPPD 90 Degree Detectors(1Hz, 9 hours) Neutron Beam Profile Measured By the first Monitor in SANS Wavelength Spectrum of MR Straight Beam With Slits by Main Detector CTOF Neutron Spectrum of Coupled Hydrogen Moderator Proton Beam Imaging Taken by the Target Imaging System