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The XENON1T excess can be explained by the Axion Like Particle (ALP) darkmatter with mass around 2.5 keV. However, there are three problems needed to besolved: suppressing the coupling $g_{a\gamma}$ between the ALP and photon, andgenerating the proper coupling $g_{ae}$ between the ALP and electron as well asthe correct ALP mass. We propose three models to solve these problems. In ourmodels, the $g_{ae}$ couplings are produced by integrating out the vector-likeleptons, and the correct ALP masses arise from high-dimensional operators. Inthe KSVZ axion model, the coupling $g_{a\gamma}$ can be suppressed by choosingproper sets of vector-like fermions, but we need some fine-tunings to obtainthe ALP mass. Similarly, one can study the DFSZ axion model. In the $Z_8$ and $U(1)_X$ models with approximate Pseudo-Nambu-Goldstone Bosons (PNGBs), thecoupling $g_{a\gamma}$ is suppressed due to $SU(3)_C \times U(1)_{\rm EM}$anomaly free. In the $Z_8$ model, the PNGB mass can be generated naturally atthe keV scale via the dimension-8 operator. To solve the PNGB quality problemin the $ Z_8$ model, we embed it into the model with $ U(1)_X$ gauge symmetry.

The KSVZ Axion and Pseudo-Nambu-Goldstone Boson Models for the XENON1T Excess