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Changing-look Active Galactic Nuclei (CL AGN) can be generally confirmed bythe emergence (turn-on) or disappearance (turn-off) of broad emission lines,associated with a transient timescale (about $100\sim5000$ days) that is muchshorter than predicted by traditional accretion disk models. We carry out asystematic CL AGN search by cross-matching the spectra coming from the DarkEnergy Spectroscopic Instrument and the Sloan Digital Sky Survey. Followingprevious studies, we identify CL AGN based on $\rm{H}\alpha $, $\rm{H}\beta$,and Mg\,{\sc ii} at $z\leq0.75$ and Mg\,{\sc ii}, C\,{\sc iii}], and C\,{\sciv} at $z>0.75$. We present 130 CL AGN based on visual inspection and threeselection criteria, including 2 $\rm{H}\alpha$, 45 $\rm{H}\beta$, 38 Mg\,{\scii}, 61 C\,{\sc iii}], and 10 C\,{\sc iv} CL AGN. Twenty cases showsimultaneous appearances/disappearances of two broad emission lines while threeAGN exhibit the concurrent appearance of three broad emission lines. We alsopresent 91 CL AGN candidates with significant flux variation of broad emissionlines but remaining strong broad components. In the confirmed CL AGN, 42 casesshow additional CL candidate features for different lines. In this paper, wefind 1) a 95:35 ratio of a turn-on to turn-off CL AGN; 2) the highest redshiftCL AGN ($z=3.56$) ever discovered; 3) an upper limit transition timescaleranging from 244 to 5762 days in the rest-frame; 4) the majority of CL AGNfollow the bluer-when-brighter trend. Our results greatly increase the currentCL census ($30\sim50\%$) and would be conducive to explore the underlyingphysical mechanism.

Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. I.Sample from the Early Data