The transmission characteristics of a high frequency coplanar waveguide circulator has been designed and simulated, using high-frequency electromagnetic analysis based on the finite element method. To reduce the volume of the circulator, we dramatically reduced the thickness of the YIG ferrite layer (Yttrium Iron Garnet), with saturation magnetization of 0.1750 T and a magnetic field of 557 kA/m, in order to get a 10 µm-thick film. The circulator is hexagonal-shaped and 100 mm-wide. The width of the central line (LINE) is 0.4 mm, the space between LINE and GND is 0.15 mm. The circulator operates at 10 GHz with an acceptable nonreciprocal transmission effect. The insertion loss is 3.14 dB, the return loss is 18.57 dB and the isolation is greater than 20 dB.