A polymer comprising a repeating unit represented by the following Formula in 40 mol% to 100 mol% of the whole repeating unit forming the polymer: wherein, in Formula , * represents a bonding site with a neighboring repeating unit or an end group in the polymer; R1, R3, R4, R5, R6 and R8 each independently represent a group selected from the group consisting of a hydrogen atom, a deuterium atom, a fluorine atom, a CN group, an NRaRb group, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming atoms, and a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms, wherein Ra and Rb independently represent a group selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming atoms, and a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms; at least one of R4 and R5 is an aromatic amino group represented by the following Formula (A), in Formula (A), Ar2 and Ar3 each independently represent a substituted or unsubstituted aryl group having 6 to 30 ring-forming atoms, or a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms; and R9 and R10 each independently represent a group selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, an unsubstituted aryl group having 6 to 30 ring-forming atoms, and a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms; or R9 and R10, together with the carbon atoms in Formula to which they bond, form a substituted or unsubstituted cycloalkyl ring having 3 to 10 ring-forming atoms, or a substituted or unsubstituted spirofluorene ring, wherein a number of the whole repeating unit is an average of 10 to 1000 per one molecule. wherein, in Formula , * represents a bonding site with a neighboring repeating unit or an end group in the polymer; R1, R3, R4, R5, R6 and R8 each independently represent a group selected from the group consisting of a hydrogen atom, a deuterium atom, a fluorine atom, a CN group, an NRaRb group, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming atoms, and a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms, wherein Ra and Rb independently represent a group selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming atoms, and a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms; at least one of R4 and R5 is an aromatic amino group represented by the following Formula (A), in Formula (A), Ar2 and Ar3 each independently represent a substituted or unsubstituted aryl group having 6 to 30 ring-forming atoms, or a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms; and R9 and R10 each independently represent a group selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, an unsubstituted aryl group having 6 to 30 ring-forming atoms, and a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms; or R9 and R10, together with the carbon atoms in Formula to which they bond, form a substituted or unsubstituted cycloalkyl ring having 3 to 10 ring-forming atoms, or a substituted or unsubstituted spirofluorene ring, wherein a number of the whole repeating unit is an average of 10 to 1000 per one molecule. <EOS>