The invention discloses a Kovar core column grid-control X-ray tube. The Kovar core column grid-control X-ray tube comprises a glass shell (3), a positive electrode assembly and a negative electrode assembly; the negative electrode assembly comprises a Kovar core column (1) and a negative electrode cover (2); the positive electrode assembly comprises a positive electrode cap (4), a positive electrode target assembly (5) and a positive electrode Kovar packaging part (6); the positive electrode cap (4) and the positive electrode Kovar packaging part (6) are fixed with the positive electrode target assembly (5) separately; the Kovar core column (1) comprises a single-glass-bead dual-filament structure (11) and a core column plate (12); the single-glass-bead dual-filament structure (11) is fixed on the core column plate (12); and the single-glass-bead dual-filament structure (11) mainly consists of a single glass bead (111) and two filaments (112) in a fixing packaging manner. The negativeelectrode of the Kovar core column grid-control X-ray tube adopts the single-glass-bead dual-filament Kovar core column structure, so that reliability of the negative electrode packaging process of the x-ray tube and working reliability of the finished product of the tube can be improved.