In this manuscript, we report evidence to support the dependence of Dn4000 (4000 Å break strength to trace stellar ages) on central active galactic nuclei (AGN) activity traced by narrow emission line properties in local Type-2 AGN in SDSS DR16. Based on the measured Dn4000 and flux ratios of [O iii] to narrow Hβ (O3HB) and [N ii] to narrow Hα (N2HA) and narrow Hα line luminosity LHα, linear dependence of the Dn4000 on the O3HB, N2HA and LHα in the local Type-2 AGN can provide clues to support the dependence of Dn4000 on properties with narrow emission lines. Linear correlations between the Dn4000 and the O3HB and N2HA can be found in the local Type-2 AGN, with Spearman rank correlations of about −0.39 and 0.53. Meanwhile, stronger dependence of the Dn4000 on the LHα can be confirmed in Type-2 AGN, with a Spearman rank correlation coefficient of about −0.7. Moreover, combining the LHα and the N2HA, a more robust and stronger linear correlation can be confirmed between the Dn4000 and the new parameter , with a Spearman rank correlation coefficient of about −0.76 and with smaller rms scatters. After considering necessary effects,the dependence of Dn4000 on LR is stable and robust enough for the local Type-2 AGN,indicating that the LR on the narrow emission lines can be treated as a better indicator to statistically trace stellar ages of samples of more luminous AGN with weaker host galaxy absorption features.

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