A one-dimensional position-sensitive ionization chamber has been designed and fabricated.The cathode of this ionization chamber consists of two selfsame units that are insulated from each other and each unit is divided into two-way cleft plates.From current output signals, it can offer the intensity and position of X-ray beam.The ionization chamber was installed on a SSRF macromolecular crystallography beamline and its performance was tested.In the test,a standard ionization chamber was used for the comparison of beam intensity measurement.The one-dimensional position-sensitive ionization chamber was fixed on a high precision linear motor stage and was driven on horizontal direction to scan the beam position step by step, In which the beam energy was set to be 8 keV and the scanning range to be 10 mm.The position scan was repeated 12 times.The tested specifications were plateau curves, linearity, position resolution and the intensity of beam.The results indicate that the 1-D position-sensitive ionization chamber has a good linearity and its position resolution is better than 20 μm and linear measuring range is 6 mm.Moreover,it will be installed on the beamline of SSRF for monitoring the stability of beam.