The corona characteristic of HVDC tube bus is the main factor taken into account for choosing tube bus of HVDC converter substation. The intension of corona could affect the electromagnetic environment of converter station and generate audible noise. By establishing the calculation models of electric field strength along the tube bus surface and the electric field strength on ground, the paper computes the corona onset voltage gradient and gives the relation curve of high and electrode spacing of tube bus. If the tube bus in HVDC converter substation is installed at the high and electrode spacing, got by the relation curve, it will not generate corona and its electric field strength will meet the requirements. The control indexes of tube bus corona characteristic parameters for HVDC converter substation are confirmed in combination with calculation results and related standards. Based on the control indexes, the paper gives the collocations of different tube bus types.