Acicular barium ferrite fine particles doped with Co2+ ions and Ti4+ ions were prepared by a conventional sintering method. Magnetic properties and crystal structure of the acicular BaCoXTiXFe12-2X O19 (X=0-1.0) particles were investigated. These particles had long axis of about 0.8μm and aspect ratio of about 11. The size of acicular fine particles did not changed with doping content of Co2+ and Ti4+ ions. The magnetization for the acicular BaCoXTiXFe12-2X O19 particles had same value of about 0.33 Wb/m2, but the coercive force of them was decreased from 310 kA/m to 35 kA/m with increase of doping content. In addition, crystal structure of them were investigated. From x-ray diffraction patterns, the acicular BaCoXTiXFe12-2XO19 particles had hexagonal structure of the magnetoplumbite. It was observed by dark field images of TEM that the acicular BaCoXTiXFe12-2XO19 particle consisted of some crystallites and the c-axis of them were normal to the long axis of an acicular particle.