In this work,we calculate the sub-leading power contributions to radiative leptonic D→γlv decay.For the first time,we provide the analytic expressions of next-to-leading power contributions and the error estimation associated with the power expansion of O(A;/m;).In our calculation,we adopt two different models of the Dmeson distribution amplitudes Φ;and Φ;.Within the framework of QCD factorization as well as the dispersion relation,we evaluate the soft contribution up to the next-to-leading logarithmic accuracy and also consider the higher-twist contribution from the two-particle and three-particle distribution amplitudes.Finally,we find that all the sub-leading power contributions are significant at λ;(μ;)=354 MeV,and the next-to-leading power contributions lead to 143% in Φ;+ and 120% in Φ;corrections to leading power vector form factors with E;=0.5 GeV.As the corrections from the higher-twist and local sub-leading power contributions are enhanced with increasing inverse moment,it is difficult to extract an appropriate inverse moment of the D-meson distribution amplitude.The predicted branching fractions are(1.88;) × 10;for Φ;and(2.31;)× 10;for Φ;.