Intensified drought stress threatens plant growth and productivity, while elevated CO2 (e[CO2]) alleviates the negative impact of drought stress on plants through alteration in water use and improvement in plant growth. In the terrestrial ecosystem, crops are particularly sensitive to drought and benefit from e[CO2]. To cope with the drier and CO2-enriched climate, plants have evolved various adaptive strategies. Water-dependent crops can benefit from e[CO2] but are species-dependent and depend on the intensities and durations of drought stress. In this chapter, we summarized drought impact on crops, crop performance under e[CO2], as well as their interactions in physiological, biochemical, and molecular levels.