The invention discloses a high-hardness easily-scrubbed interior wall coating for a kitchen and a preparation method. The coating comprises, in weight percentage, 14-24% of water, 0.4-0.6% of wetting dispersants, 0.2-0.25% of cellulose, 0.1-0.2% of defoaming agents, 0.8-1.2% of anti-freezing agents, 0.3-0.6% of scratch-resistant agents, 0-10% of titanium dioxide, 20-30% of calcite in powder, 0.1-0.2% of pH (potential of hydrogen) conditioning agents, 40-50% of silane-siloxane emulsion, 2-2.5% of coalescing agents, 0.5-1% of mildew-proof agents, 0.1-0.3% of sterilizing agents, 0.2-0.4% of water repellent agents and 0.2-0.3% of anti-doodling agents. According to the emulsion, reactivity and permeability of silane and flowability and water drop effect of siloxane can be combined, molecular volume is minimum, the surfaces of substrates are coated with the emulsion, the emulsion can deeply permeate into the substrates, and reaction between the emulsion and the substrates and between the emulsion can be achieved, so that durability is achieved. After emulsion is cured, permeation of water vapor is allowed, liquid water possibly containing chloride ions or acid after dissolution is prevented from permeating into the substrates, condensation reaction between silane can be achieved to form Si-O-Si polymers, the silane facing the outer side of the surface can effectively drain water, and protection for freezing and thawing damage, permeation, oil penetration and mildew can be provided.