L-Cysteine solubility in 12 monosolvents (water, methanol, ethanol, n-propanol, n-butanol, sec-butanol, isopropanol, isobutanol, ethyl acetate, 1,4-dioxane, acetonitrile, and acetone) and three binary solvents (water + methanol, water + ethanol, and water + isopropanol) was determined by the gravimetric method from 283.15 to 323.15 K under the atmospheric pressure. The solubility order in pure solvents was acetonitrile < isobutanol < ethyl acetate approximate to sec-butanol < n-butanol < 1,4-dioxane < isopropanol < n-propanol < ethanol < methanol < acetone < water, and it was positively related to the experimental temperature and solvent composition for all solvent systems. For polar protic solvents, the key factors influencing the solubility were the length of the carbon chain and the solvent properties. The effect of solvent- solvent and solvent-solute intermolecular interactions on the solubility behavior was analyzed by the KAT-LSER model. The modified Apelblat, Jouyban-Acree, and Apelblat-Jouyban-Acree models were used to correlate the solubility data, and the values calculated by the three thermodynamic models were found to agree well with the experimental data.