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G213.0$-$0.6 is a faint extended source situated in the anti-center region ofthe Galactic plane. It has been classified as a shell-type supernova remnant(SNR) based on its shell-like morphology, steep radio continuum spectrum, andhigh ratio of [S II]/H$\alpha$. With new optical emission line data ofH$\alpha$, [S II], and [N II] recently observed by the Large Sky AreaMulti-Object Fiber Spectroscopic Telescope, the ratios of [S II]/H$\alpha$ and[N II]/H$\alpha$ are re-assessed. The lower values than those previouslyreported put G213.0$-$0.6 around the borderline of SNR-HII regionclassification. We decompose the steep-spectrum synchrotron and theflat-spectrum thermal free-free emission in the area of G213.0$-$0.6 withmulti-frequency radio continuum data. G213.0$-$0.6 is found to show a flatspectrum, in conflict with the properties of a shell-type SNR. Such a result isfurther confirmed by TT-plots made between the 863-MHz, 1.4-GHz, and 4.8-GHzdata. Combining the evidence extracted in both optical and radio continuum, weargue that G213.0$-$0.6 is possibly not an SNR, but an HII region instead. The$V_{LSR}$ pertaining to the H$\alpha$ filaments places G213.0$-$0.6approximately 1.9 kpc away in the Perseus Arm.

G213.0$-$0.6, a true supernova remnant or just an HII region?