Carbon storage in crops is an important component of global carbon stock in terrestrial ecosystems. Three methods are frequently used for estimating the carbon stock in crops of China: parametric evaluation, remote sensing inversion, and simulation modeling based on environmental parameters. Based on recent research into crop carbon storage estimations at the national to regional levels in last decades in China, specific parameters for estimating the carbon stock of several crops have been obtained. These parameters include the economic coefficient, carbon ratio and water ratio of the harvested parts of several crops. Both remote sensing inversion and simulation modeling methods have been explored. And some countermeasures for stabilizing and increasing carbon storage in crops have been suggested. These countermeasures include: stabilizing crop production through enhancing agrarian infrastructure, improving agricultural technology and management standards, developing eco-agriculture to increase crop productivity, adjusting cropping structure, expanding the sown areas of rice, rape and potato while maintaining current sown area of wheat, and increasing the efficiency of use of crop stalks. Uncertainty and inaccuracy are major challenges in crop carbon estimations of China, parameters used for estimations are still limited, and methods and models for carbon estimations need to be further improved. There is no consensus on the source-sink effects of the dynamic process of crop carbon storage. Although soil carbon storage (or density) in farmland is generally greater than crop vegetation carbon storage, the storage capacity of crop vegetation is tremendous and thus has great potential to become an increasingly important carbon sink. This potential and the efficiency of use of straw stalks directly impact on soil carbon stock. So analysis of crop carbon storage needs to focus on its tempo-spatial disparity to understand the source-sink effects of carbon dynamics. Future studies should address issues of: improved methods and models for carbon estimation; empirical evidence in estimating carbon storage and best practice in increasing carbon storage at the regional level; methods for scale transformation in carbon storage estimations of crop vegetation between different spatial scales; and integral research into the mechanisms for carbon concentrations and dynamics of crop vegetation. Studying the nexus between climate change and its impact on carbon storage in crops is also urgently needed.