Objective：To assess the structure and function remodeling of left atrial（LA）and left atrial appendage（LAA）using cardiac CT in patients with atrial fibrillation（AF），and to evaluate its relation with stroke. Methods：We retrospectively analyzed the CT imaging of 221 patients with AF and divided them into the stroke group and the non-stroke group. The left atrium maximum volume（LAVmax），left artium minimum volume（LAVmin），left artrium appendage maximum volume（LAAVmax）and left artrium appendage minimum volume（LAAVmin）were segmented and measured by post-processing software. The LA and LAA ejection fractions（LAEF，LAAEF）and LAA were calculated. According to the shape of the appendage，we divided LAA into chicken wings and non-chicken wings. And whether there was a thrombus or circulatroy stasis in LAA was also observed. Univariate and multivariate statistical analyses were carried out on the parameters of LA. Results：Among the 221 patients with AF，47 patients developed a stroke. The LAVmax and LAVmin in the stroke group were significantly larger than those in the non-stroke group（P < 0.05），LAEF in the stroke group decreased compared with the non-stroke group（P < 0.05）. The proportion of non-chicken wing type in the stroke group was higher than that in the non-stroke group（P=0.006）. The proportion of thrombosis or pre-thrombotic state in the LA of the stroke group was higher than that in the non-stroke group（P=0.01）. The LA volume，LAA structure，and LAA hemodynamic status were independently associated with stroke. Conclusion：LA parameters measured by cardiac CT may be useful for predicting stroke in patients with AF.