A spiro structure compound represented by the following Chemical Formula 1: in Chemical Formula 1, X1 is O or S, R1 to R4 are the same as or different from each other, and are each independently hydrogen; deuterium; a nitrile group; a nitro group; a hydroxy group; a carbonyl group; an ester group; an imide group; an amide group; a substituted or unsubstituted alkyl group; a substituted or unsubstituted cycloalkyl group; a substituted or unsubstituted alkoxy group; a substituted or unsubstituted aryloxy group; a substituted or unsubstituted alkylthioxy group; a substituted or unsubstituted arylthioxy group; a substituted or unsubstituted alkylsulfoxy group; a substituted or unsubstituted arylsulfoxy group; a substituted or unsubstituted alkenyl group; a substituted or unsubstituted silyl group; a substituted or unsubstituted boron group; a substituted or unsubstituted amine group; a substituted or unsubstituted arylphosphine group; a substituted or unsubstituted phosphine oxide group; a substituted or unsubstituted aryl group; or a substituted or unsubstituted heteroaryl group, L1 to L3 are the same as or different from each other, and are each independently a direct bond; a substituted or unsubstituted arylene group; or a substituted or unsubstituted heteroarylene group, Ar1 to Ar6 are the same as or different from each other, and are each independently a substituted or unsubstituted aryl group; or a substituted or unsubstituted heteroaryl group, or one or more of Ar1 and Ar2; Ar3 and Ar4; and Ar5 and Ar6 combine with each other to form a substituted or unsubstituted ring, r1, r2, r3, and r4 are each an integer of 1 to 4, m, n, and p are each an integer of 0 to 3, m + n + p ≥ 2, if m=1, then n=0, if m=0, then n=1, and when r1, r2, r3, r4, m, n, and p are each an integer of 2 or more, two or more structures in the parenthesis are the same as or different from each other. X1 is O or S, R1 to R4 are the same as or different from each other, and are each independently hydrogen; deuterium; a nitrile group; a nitro group; a hydroxy group; a carbonyl group; an ester group; an imide group; an amide group; a substituted or unsubstituted alkyl group; a substituted or unsubstituted cycloalkyl group; a substituted or unsubstituted alkoxy group; a substituted or unsubstituted aryloxy group; a substituted or unsubstituted alkylthioxy group; a substituted or unsubstituted arylthioxy group; a substituted or unsubstituted alkylsulfoxy group; a substituted or unsubstituted arylsulfoxy group; a substituted or unsubstituted alkenyl group; a substituted or unsubstituted silyl group; a substituted or unsubstituted boron group; a substituted or unsubstituted amine group; a substituted or unsubstituted arylphosphine group; a substituted or unsubstituted phosphine oxide group; a substituted or unsubstituted aryl group; or a substituted or unsubstituted heteroaryl group, L1 to L3 are the same as or different from each other, and are each independently a direct bond; a substituted or unsubstituted arylene group; or a substituted or unsubstituted heteroarylene group, Ar1 to Ar6 are the same as or different from each other, and are each independently a substituted or unsubstituted aryl group; or a substituted or unsubstituted heteroaryl group, or one or more of Ar1 and Ar2; Ar3 and Ar4; and Ar5 and Ar6 combine with each other to form a substituted or unsubstituted ring, r1, r2, r3, and r4 are each an integer of 1 to 4, m, n, and p are each an integer of 0 to 3, m + n + p ≥ 2, if m=1, then n=0, if m=0, then n=1, and when r1, r2, r3, r4, m, n, and p are each an integer of 2 or more, two or more structures in the parenthesis are the same as or different from each other. <EOS>