A search for Higgs boson (H) production at high transverse momentum (pT) in the WW decay channel is presented. The analysis uses proton-proton collisions at √s = 13 TeV recorded by the CMS experiment in 2016–2018, corresponding to an integrated luminosity of 138 fb−1. The visible decay products of the Higgs boson are reconstructed as a single large-radius jet with one isolated lepton or none (1ℓ and 0ℓ, respectively; ℓ = e, μ). The H-candidate jets are identified using an advanced transformer-based algorithm and are calibrated with the Lund jet plane reweighting technique. The 1ℓ channel is further split into gluon fusion, vector boson fusion, and associated production with hadronically decaying vector boson categories, while the 0ℓ channel considers all production processes inclusively. The measured cross section times the H → WW branching fraction relative to the standard model expectation is µ = −0.19^+0.48_-0.46 , indicating no evidence of a signal above the background. This measurement represents the first dedicated study of highly Lorentz-boosted H → WW decays, complementing earlier searches for high-pT Higgs boson in other decay channels.