The invention relates to an asymmetric dioxime ester compound shown as general formula I and a making method thereof. In the general formula I, Ar1 is X1 substituted C6-C20 o-
arylene or C3-C20 o-heteroarylene; Ar2 is C6-C20
arylene or C3-C20 heteroarylene, is connected to Ar1 through X1, or at the same time of connection to Ar1 through X1, the Ar2
carbon atom adjacent to the
substituent group X1 is in connection with Ar1 through an axial bond,
carbon atom, carbonyl, O, S and NR18 to form a cyclic structure; n is 0 or 1; X1 is NR18, O, S, C=O or S=O; Y1 is (CH2)mCR15R16, NR19, O(CR15R16)m, S(CR15R16)m, (CR15R16)m C=O, S=O; m is 0 or 1; R1, R2 and R3 are respectively
hydrogen atom,
alkyl or alkoxy, arbitrary group substituted
alkyl or alkoxy, cycloalkyl, arbitrary group substituted
aryl, and acyl. The invention also relates to a photocurable composition with the general formula I compound as the
photoinitiator. The composition is used for preparation of
photoresist devices like color filters for display screens, and shows very high curing sensitivity. (formula I as shown in the specification).