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Cosmological CPT violation will rotate the polarized direction of CMB photons, convert partial CMB E mode into B mode and vice versa. It will generate non-zero EB, TB spectra and change the EE, BB, TE spectra. This phenomenon gives us a way to detect the CPT-violation signature from CMB observations, and also provides a new mechanism to produce B mode polarization. In this paper, we perform a global analysis on tensor-to-scalar ratio r and polarization rotation angles based on current CMB datasets with both low ℓ (Planck, BICEP2/Keck Array) and high ℓ (POLARBEAR, SPTpol, ACTPol). Benefited from the high precision of CMB data, we obtain the isotropic rotation angle α¯=0.0∘±0.37∘ at 68% CL, the variance of the anisotropic rotation angles Cα(0)<0.0032rad2, the scale invariant power spectrum Dℓ∈[2,350]αα<4.65×10−5rad2 and r<0.059 at 95% CL. Our result shows that with the polarization rotation effect, the 95% upper limit on r gets tightened by 14%. Keywords: Primordial gravitational waves, CPT symmetry violation, Polarization rotation angle, Global fitting, High ℓ CMB power spectra