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• Obtained H 2 -broadened CH 4 spectra in the v 2 + v 3 band (2.2 µm) at 80 – 370 K. • Fit 28 spectra simultaneously and achieved spectrum fitting residuals better than 1%. • Retrieved H 2 -broadened widths, H 2 -pressue shifts, and their temperature dependences. • Determined collisional line mixing coefficients through full line mixing operation. • Showed J and A/E/F dependence of H 2 -widths for CH4 in the v2+v3 band. We have made the measurements of H 2 -broadened line shape parameters of CH 4 transitions in the v 2 + v 3 band located at 2.2 µm. These measurements support atmospheric opacity calculations of cold giant planets, hot Jupiters, and low mass brown dwarfs, for which H 2 is the dominant atmospheric constituent. For this reason, a series of spectra of pure CH 4 and CH 4 H 2 mixtures were obtained in the Octad (4100–4600 cm−1) region for a wide temperature range between 80 and 370 K using a Bruker 125HR high-resolution Fourier transform spectrometer (FTS) at Jet Propulsion Laboratory (JPL). Three custom-designed gas absorption cells vacuum-coupled to the FTS were used to obtain the spectra. All spectra were fit simultaneously using a multispectrum non-linear least-squares fitting software, which adopts a speed-dependent Voigt line shape using full line mixing taken into account through a relaxation matrix operation. H 2 pressure broadened half-widths, and H 2 pressure-induced shift coefficients were determined in 11 J-manifolds covering P(4) – R(6) plus the Q-branch. The temperature dependences of the width and shift coefficients were determined based upon the power law and the linear models. Collisional line mixing coefficients for CH 4 H 2 were retrieved for ten transition pairs. For the same transitions, speed dependence parameters for the CH 4 H 2 transitions were found to be smaller than for CH 4 -air-broadening. We have compiled the retrieved line parameters in an electronic format and reported as supplemental document. This will facilitate the analyses of planetary and exoplanetary atmospheres using ground-, air- and space-based observations (e.g., Keck I and II, SOFIA, JWST). Image, graphical abstract Figure. Spectrum fitting residuals in the R(6) manifold. (a) with no line mixing, (b) with line mixing, In the bottom panel the observed and calculated spectra where two pairs of transitions mix together, e.g., F 1 and F 2 , and A 1 and A 2 are labeled. The vertical bars (in black at the top of the bottom panel) represent the locations of all transitions included in the calculations. The vertical bars in red, blue, and green indicate the line position of the 1st, 2nd and 3rd sets of five strongest lines each group, respectively. [ Colors available in the online version ]. [ABSTRACT FROM AUTHOR]