A cathode control multi-cathode distributed X-ray apparatus, comprising: a vacuum box with the perimeter sealed and a high vacuum inside, a plurality of cathodes (1, 11, 12) independent of each other and arranged as a linear array and mounted at one end inside the vacuum box, each cathode (1, 11, 12) having a cathode filament, a cathode surface connected to the cathode filament and a filament lead drawn out from both ends of the cathode filament; a plurality of focal current limiters (2, 21, 22) arranged as a linear array corresponding one by one to the cathodes (1, 11, 12) and mounted at a position near the cathodes (1, 11, 12) in the middle part inside the vacuum box, the focal current limiters (2, 21, 22) being connected to one another; an anode made of metal and mounted at another end inside the vacuum box, being parallel to the focal current limiters (2, 21, 22) in the length direction and forming an included angle of predetermined degrees with the focal current limiters (2, 21, 22) in the width direction; a power supply and control system, having a cathode power supply (PS1, PS2, PS3), a focal current limiter power supply connected to the interconnected focal current limiters (2, 21, 22), an anode high voltage power supply (+H.V.), and a control apparatus for exercising comprehensive logical control over the respective power supplies; a pluggable high voltage connector, for connecting the anode to the anode high voltage power supply (+H.V.), and installed at the side face of one end of the vacuum box near the anode; and a plurality of pluggable cathode power supply connectors (6, 61, 62), for connecting the cathode (1, 11, 12) to the cathode power supply (PS1, PS2, PS3), and installed at the side face of one end of the vacuum box near the cathode (1, 11, 12), characterised in that: the cathodes (1, 11, 12) further comprise: a cathode housing, surrounding the cathode filament and the cathode surface, and the housing cmprising a beam stream aperture being disposed at a position corresponding to the center of the cathode surface, a planar structure being disposed at the outer edge of the beam stream aperture, a slope being disposed at the outer edge of the planar structure; a cathode shield outside the cathode housing, surrounding other faces besides the one having a beam stream aperture of the cathode housing, the filament lead passes through the cathode housing and the cathode shield is drawn out to the pluggable cathode power supply connectors (6, 61, 62). a vacuum box with the perimeter sealed and a high vacuum inside, a plurality of cathodes (1, 11, 12) independent of each other and arranged as a linear array and mounted at one end inside the vacuum box, each cathode (1, 11, 12) having a cathode filament, a cathode surface connected to the cathode filament and a filament lead drawn out from both ends of the cathode filament; a plurality of focal current limiters (2, 21, 22) arranged as a linear array corresponding one by one to the cathodes (1, 11, 12) and mounted at a position near the cathodes (1, 11, 12) in the middle part inside the vacuum box, the focal current limiters (2, 21, 22) being connected to one another; an anode made of metal and mounted at another end inside the vacuum box, being parallel to the focal current limiters (2, 21, 22) in the length direction and forming an included angle of predetermined degrees with the focal current limiters (2, 21, 22) in the width direction; a power supply and control system, having a cathode power supply (PS1, PS2, PS3), a focal current limiter power supply connected to the interconnected focal current limiters (2, 21, 22), an anode high voltage power supply (+H.V.), and a control apparatus for exercising comprehensive logical control over the respective power supplies; a pluggable high voltage connector, for connecting the anode to the anode high voltage power supply (+H.V.), and installed at the side face of one end of the vacuum box near the anode; and a plurality of pluggable cathode power supply connectors (6, 61, 62), for connecting the cathode (1, 11, 12) to the cathode power supply (PS1, PS2, PS3), and installed at the side face of one end of the vacuum box near the cathode (1, 11, 12), characterised in that: the cathodes (1, 11, 12) further comprise: a cathode housing, surrounding the cathode filament and the cathode surface, and the housing cmprising a beam stream aperture being disposed at a position corresponding to the center of the cathode surface, a planar structure being disposed at the outer edge of the beam stream aperture, a slope being disposed at the outer edge of the planar structure; a cathode shield outside the cathode housing, surrounding other faces besides the one having a beam stream aperture of the cathode housing, the filament lead passes through the cathode housing and the cathode shield is drawn out to the pluggable cathode power supply connectors (6, 61, 62).