We present the [O II] (lambda lambda 3729; 3726) luminosity function measured in the redshift range 0.1 < z < 1.65 with unprecedented depth and accuracy. Our measurements are based on medium resolution flux-calibrated spectra of emission line galaxies with the visual and near UV FOcal Reducer and low dispersion Spectrograph (FORS2) for the Very Large Telescope (VLT) of the European Southern Observatory (ESO) and with the SDSS-III/BOSS spectrograph. The FORS2 spectra and the corresponding catalog containing redshifts and line fluxes are released along with this paper. In this work we use a novel method to combine these surveys with GAMA, zCOSMOS, and VVDS, which have di ff erent target selection, producing a consistent weighting scheme to derive the [O II] luminosity function. The [O II] luminosity function is in good agreement with previous independent estimates. The comparison with two stateof- the-art semi-analytical models is good, which is encouraging for the production of mock catalogs of [O II] flux limited surveys. We observe the bright end evolution over 8.5 Gyr: we measure the decrease of log L-* from 42.4 erg/s at redshift 1.44 to 41.2 at redshift 0.165 and we find that the faint end slope flattens when redshift decreases. This measurement confirms the feasibility of the target selection of future baryonic acoustic oscillation surveys aiming at observing [OII] flux limited samples.