•Line strengths of CH3D transitions at selected regions are reported.•CH3D indicates very different absorption features from both CH4 and 13CH4.•Absolute line strengths of CH3D are weaker than those of CH4 and 13CH4.•Pressure-broadening and pressure-shift coefficients were also measured.Three DFB near-IR lasers were used to measure the line strengths of CH3D ro-vibrational transitions (2ν4) in the wavenumber regions of 6017.5–6031.5 cm−1 and 6046.5–6070.0 cm−1 using continuous-wave cavity ring-down spectroscopy (cw-CRDS). In the wavenumber interval of 6017.5–6031.5 cm−1, the strongest peak is located at 6024.697 cm−1 with a line strength of 1.24 × 10−25 cm/molecule of CH4, assuming a CH3D natural abundance of 0.0616%. In the 6046.5–6060.0 cm−1 interval, the strongest peak is located at 6055.178 cm−1 with a line strength of 9.31 × 10−26 cm/molecule. In the 6060.5–6070.0 cm−1 interval, the strongest peak is located at 6066.538 cm−1 with line strength of 2.27 × 10−25 cm/molecule. We measured foreign gas pressure-broadening and pressure-shift coefficients of CH3D absorption lines. The N2, O2 and CO2 pressure-broadening coefficients of CH3D are 0.064(1), 0.060(1) and 0.061(5) cm−1/atm, respectively, at the wavenumber of 6017.941 cm−1 and 0.051(1), 0.052(1) and 0.046(2) cm−1/atm, respectively, at the wavenumber of 6064.286 cm−1. The N2 and O2 pressure-broadening coefficients of CH3D are 0.065(2) and 0.060(1) cm−1/atm, respectively, at the wavenumber of 6066.538 cm−1. The N2, O2 and CO2 pressure-shift coefficients of CH3D at the wavenumber of 6032.443 cm−1 are −0.012(1), −0.012(1) and −0.013(1) cm−1/atm, respectively.Graphical abstract