Objective:This stndy aims to evaluate the value of compressed sensing(CS) cine cardiac magnetic resonance(CMR) for left atrial(LA)functional assessment compared with traditional segmented cine imaging(regarded as gold standard). Methods:Forty healthy volunteers and thirty-one patients with reduced left ventricular diastolic function by echocardiography underwent segmented cine and CS cine imaging with steady-state free-precession sequence to cover LA during CMR. LA diameter,volume and ejection fraction(EF)were evaluated by CVI42(circle cardiovascular imaging,Canada). Two radiologists independently performed qualitative analysis of image quality and quantitative analysis of all above LA parameters. Results:The image quality was no significant difference between traditional and CS cine. There was an excellent correlation for LA diameter(ICC>0.90) and good correlation for LA volume,EF between both cines(ICC>0.80),except for active EF. There were no significant difference in LA 2- and 4-chamber transverse diameters derived from both cines. Compared to the gold standard,the CS cine overestimated LA minimal volume,but the difference was small[(4.45±11.18)mL,P=0.003]. The LA maximal volume,pre-active volume and passive EF obtained by the two methods had no statistical difference. CS cine more accurately distinguished volunteers from patients with abnormal LA function than segmented cine. Conclusion:CS cine can be used to accurately evaluate LA diameter and volume for LA functional assessment,especially passive EF of LA.