Abstract: The influence of the geometrical parameters, the inscribed circle diameter D and the cell wall thickness t,on the density and strength of the honeycomb unit made with Tibased alloy was investigated.It was found that when D was large and t was thin, the microstructure of the weld interface was discontinuous and differed in grain sizes,which would seriously deteriorate the strength of the honeycomb unit.The unit strength could be expressed as σ=118.8×t_-3.44 when D was 11.2 mm, or σ=262.8×t_-5.94 when D was 6.4 mm.High specific strength was obtained with D as 4.8 mm and t as 0.05 mm.The quantitative relation between the geometrical parameters and specific strength could be estimated by the specific strength of the honeycomb unit with Ti-based alloys.