Most measurements or studies on the traits of plants and animals in nature have been limited to the levels of organ or species, although many studies have demonstrated that functional trait of plants and animals played important roles in adjusting external environments and optimizing productivity among the organ, to the species, community, and ecosystem levels. More importantly, climate change, land-use change, and atmospheric nitrogen and acid deposition have strong ecological and environmental effects at the widest range of scales, from the region to the globe. Thus, integration of the study of traditional functional traits with new technologies of macro-ecological research, such as ecological modeling, eddy-flux observation, and remote sensing is urgently required. To resolve the gaps between the study of traditional traits and macro-ecological research, mainly unit and scale mismatch, scientists recently proposed a framework for quantifying "ecosystem traits" (ESTs) and the means to address the challenges of broadening the applicability of functional traits to macro-ecology. Ecosystem traits here are defined as traits or quantitative characteristics of organisms (plants, animals, and microbes) at the community level expressed as the intensity (or density) normalized per unit land area. Furthermore, a series of examples of ecosystem traits from primary data, scale-up methods, and trait-functioning relationship are provided in a novel functional trait database in China (China_Traits). In a specific ecosystem, ecosystem traits comprise the plant community trait, animal community trait, microbial community trait, soil, and environmental parameters. It is undeniable that there are still problems or challenges with the new concept frame and related methods, as in any new field in science. Importantly, this new concept or idea of ecosystem traits helps scale-up the traditional trait from the organ to the community level, which can help better exploration of the variation and underlying mechanisms of traits at various scales from organ, to species, community, and ecosystems. Additionally, ecosystem traits can inter-relate and integrate data from field trait surveys, eddy-flux observation, remote sensing, and ecological models, and thereby provide new resolution of the responses and feedback at the regional to global scale. However, as a newly emerging approach, it is undeniable that a series of problems and challenges need to be resolved. We therefore call for further research efforts, especially from the perspective of animal and microbial community traits, to expand the robustness of this concept. In this study, we explain and develop the primary concept of ecosystem traits, and assess its theoretical significance and potential challenges, which may help improve it and promote the application of this new framework of trait-based ecosystem ecology at home and abroad.