Four kinds of ink-jet papers with different surface characteristics are chosen in this paper, by the ink-jet proofing experiments, the influence of surface characteristics to dot gain is studied, and the law of dot gain with paper surface characteristics is discussed. During the experiment, surface properties including absorbency, gloss, roughness and whiteness are tested firstly; then, the standard wedge of GATF is printed on these papers in the same printing conditions; finally, the dot gain is tested by SpectroEye. After experimental data processing and analysis, dot gain curves of different ink-jet papers are concluded, the law of dot gain with ink-jet paper surface characteristics is summarized. The results show that dot gain is different in different paper, the evaluation of 3# is the best; dot gain is also different with different colors in the same paper, and it is serious in cyan but light in yellow; the biggest dot gain appears in different contrast with different colors, cyan appears near the 65% dot area. The result of this paper offers a certain theoretical reference and practical guidance to the selection, the research and development of ink-jet paper as well as the improvement of ink-jet qualities.