Absorption oscillator strengths for thirty rotational lines in nine vibrational bands of the Lyman transition, B 1Σu+, of H2 have been obtained from equivalent widths measured photoelectrically under high resolution. Argon and helium continua were used in the third and first orders, respectively, of the grating. A curve-of-growth analysis of the measured equivalent widths of the Doppler-broadened lines yielded the f values. Our results are in agreement with electron-scattering data obtained by Geiger and Topschowsky; consequently, there is now strong evidence from absorption f value and emission lifetime data for a significant variation of dipole transition moment with internuclear separation in the Lyman transition.