The invention provides a zero-carbon emission system and method of nuclear energy-coal produced fuel chemicals. The method comprises the following steps: heating pre-heated raw water by adopting a high-temperature gas-cold-batch heat exchange system; conveying the heated raw water into a solid oxide electrolytic cell and carrying out electrolysis reaction to generate hydrogen gas and oxygen gas; conveying the oxygen gas into a coal gasification furnace and carrying out gasification reaction on the oxygen gas and coal powder to generate crude coal gas; purifying the crude coal gas into pure crude coal gas through a crude coal gas purification device; then carrying out desulfurization and purification treatment in a desulfurization and purification device; mixing the hydrogen gas and the pure crude coal gas subjected to the desulfurization and purification treatment in a mixer to obtain mixed purified gas; inputting the mixed purified gas into a fuel chemical synthesis tower and reacting. According to the zero-carbon emission system and method provided by the invention, almost hydrogen of zero-carbon emission is provided by adopting nuclear energy, and a hydrogen-carbon ratio of synthetic gas is adjusted after the hydrogen is mixed with the pure crude coal gas with the low hydrogen-carbon ratio from coal gasification, so that a water-coal gas conversion system and a high-energy-consumption air separation system in traditional coal chemical production are cancelled, and furthermore, the energy consumption of a production system is reduced and direct carbon dioxide emission ofthe system is reduced.