A method for blending coals for cokemaking, comprising: blending a plurality of coals to prepare a coal blend for use in cokemaking; determining the surface tensions of the plurality of the coals, and determining types and blending ratios of the coals to be blended based on a difference between surface tensions of the plurality of coals after heat treatment by either blending a mixture of plural coals with additional coal for cokemaking and selecting the additional coal such that the difference between the surface tension of the coal mixture of the plural coals after heat treatment and the surface tension of the additional coal after heat treatment is 1.5 mN/m or less, or wherein the plurality of coals are selected and blended such that the surface tensions of all of the plurality of coals after heat treatment fall within the range of (average - 1.5) mN/m to (average + 1.5) mN/m, where average is the average surface tension of the coals after heat treatment, or wherein the plurality of coals are blended such that the absolute difference between the surface tension of all the coals that accounts for 70% by mass or more in total in the plurality of coals after heat treatment and the average surface tension of all of the coals after heat treatment falls within the range of 0.8 mN/m or less, or wherein the plurality of coals are blended such that a total surface tension difference S determined from the surface tensions of the plurality of coals that constitute the coal blend after heat treatment and the blending ratios of the coals is 1.0 mN/m or less, the total surface tension difference S being determined by equation: [Math. 1] S = ∑ i = 1 n ∑ j = 1 n w i w j Δγ ij where w i and w j are the blending ratios of an i-th coal and a j-th coal, respectively, Δγ ij is the absolute surface tension difference between the i-th coal and the j-th coal after heat treatment, and n is the number of coals to be blended. blending a plurality of coals to prepare a coal blend for use in cokemaking; determining the surface tensions of the plurality of the coals, and determining types and blending ratios of the coals to be blended based on a difference between surface tensions of the plurality of coals after heat treatment by either blending a mixture of plural coals with additional coal for cokemaking and selecting the additional coal such that the difference between the surface tension of the coal mixture of the plural coals after heat treatment and the surface tension of the additional coal after heat treatment is 1.5 mN/m or less, or wherein the plurality of coals are selected and blended such that the surface tensions of all of the plurality of coals after heat treatment fall within the range of (average - 1.5) mN/m to (average + 1.5) mN/m, where average is the average surface tension of the coals after heat treatment, or wherein the plurality of coals are blended such that the absolute difference between the surface tension of all the coals that accounts for 70% by mass or more in total in the plurality of coals after heat treatment and the average surface tension of all of the coals after heat treatment falls within the range of 0.8 mN/m or less, or wherein the plurality of coals are blended such that a total surface tension difference S determined from the surface tensions of the plurality of coals that constitute the coal blend after heat treatment and the blending ratios of the coals is 1.0 mN/m or less, the total surface tension difference S being determined by equation: [Math. 1] S = ∑ i = 1 n ∑ j = 1 n w i w j Δγ ij where w i and w j are the blending ratios of an i-th coal and a j-th coal, respectively, Δγ ij is the absolute surface tension difference between the i-th coal and the j-th coal after heat treatment, and n is the number of coals to be blended.