Abstract: In order to explore source of CO2 gas fertilizer suitable for greenhouse production，4，6，8，10 and 12 mol/L hydrochloric acid were used to react with common building stones，relationship between gas production and CO2 generation rate after reaction of different concentrations of hydrochloric acid with stone and time，as well as mechanism of stone dissolution in reaction process were analyzed.Results showed that when volume of hydrochloric acid was the same，law of CO2 generation amount and generation rate was 12 mol/L>10 mol/L>8 mol/L>6 mol/L>4 mol/L.In greenhouse production，12 mol/L hydrochloric acid could be used to react with stones，and fertilization could be carried out through CO2 intelligent release system，so that the indoor CO2 concentration could quickly reach level required for plant growth.