Fire is the primary form of terrestrial ecosystem disturbance on a global scale and a crucial Earth system process, regulated by climate, vegetation characteristics, and human activities, while influencing climate mainly by changing the structure and functioning of terrestrial ecosystems and by emitting aerosols and trace gases. Most Earth system models (ESMs) now include fire modeling, with 19 models submitting fire-related outputs to the CMIP6. We provide the first comprehensive evaluation of CMIP6 historical fire simulations by comparing them with multiple satellite-based products and charcoal-based reconstructions. Most CMIP6 models simulate global burned area and fire carbon emissions within observed ranges, capturing spatial patterns, seasonal cycles, and response to ENSO. Regional biomass burning (BB) emissions align with charcoal-based reconstructions, although mismatches exist in South America and North America. CMIP6 models address critical CMIP5 issues, including underestimated global burned area and weak seasonal variability, but still fail to reproduce declines in burned area in recent decades and spring fire peak in NH mid-latitudes mainly due to underestimated anthropogenic fire suppression and underestimated crop fires, respectively. Improvements are also needed in estimating fire sensitivity to wet-dry conditions. Based on these findings, we present specific guidance for fire scheme development and suggest the post-processing methodology for generating reliable future BB emissions forcing data. Finally, we will introduce FireMIP in CMIP7, outlining its targets and protocol.