Studying hadron resonances in lattice QCD plays an important role in understanding exotic hadrons. We investigate baryon resonances from meson-baryon scatterings in the HAL QCD method, where we derive scattering amplitudes in lattice QCD via the interaction potentials. In this talk, I present the analysis of Δ and Ω baryons, both of which belong to the baryon decuplet. In our analysis, we use heavy quark masses so that Δ is a stable particle as well as Ω. If time permits, I also show our preliminary results of the study on Λ(1405) in flavor SU(3) limit.