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Gamma-ray bursts (GRBs) 201015A and 201216C are valuable cases with detectionof very high energy (VHE) gamma-ray afterglows. By analysing their promptemission data, we find that GRB 201216C is an extremely energetic long GRB witha hard gamma-ray spectrum, while GRB 201015A is a relative sub-energetic, softspectrum GRB. Attributing their radio-optical-X-ray afterglows to thesynchrotron radiation of the relativistic electrons accelerated in their jets,we fit their afterglow lightcurves with the standard external shock model andinfer their VHE afterglows from the synchrotron self-Compton scattering processof the electrons. It is found that the jet of GRB 201015A is mid-relativistic($\Gamma_0=44$) surrounded by a very dense medium ($n=1202$ cm$^{-3}$) and thejet of GRB 201216C is ultra-relativistic ($\Gamma_0=331$) surrounded by amoderate dense medium ($n=5$ cm$^{-3}$). The inferred peak luminosity of theVHE gamma-ray afterglows of GRB 201216C is approximately $10^{-9}$ ergcm$^{-2}$ s$^{-1}$ at $57-600$ seconds after the GRB trigger, making it can bedetectable with the MAGIC telescopes at a high confidence level, even the GRBis at a redshift of 1.1. Comparing their intrinsic VHE gamma-ray lightcurvesand spectral energy distributions with GRBs~180720B, 190114C, and 190829A, weshow that their intrinsic peak luminosity of VHE gamma-ray afterglows at$10^{4}$ seconds post the GRB trigger is variable from $10^{45}$ to $5\times10^{48}$ erg s$^{-1}$, and their kinetic energy, initial Lorentz factor, andmedium density are diverse among bursts.

Very-High-Energy Gamma-Ray Afterglows of GRB 201015A and GRB 201216C