We report ultrafast spectroscopy investigations of photoinduced exciton dynamics in three novel CH3NH3PbBr3 perovskite nanostructures: nanocrystals (0D), nanowires (1D), and nanoplatelets (2D). Aided by analysis of UV–visible absorption and photoluminescence spectra, features in the transient absorption (TA) spectra are assigned to different charge carrier processes, time constants of which are determined in fitting the transient kinetics. Immediately after photoexcitation, the charge carrier thermalization process occurs within the instrument response function time (fwhm ∼ 350 fs) and results in a quasi-equilibrium distribution of charge carriers. It is followed by charge carrier cooling on a sub-picosecond time scale (τc ∼ 300 fs). The ensuing charge carrier recombination process obeys the rate law of a second-order reaction, which suggests that it occurs mainly via the bimolecular nongeminate recombination process. Dependence of the charge recombination rate constant (kr) on the initial charge carrier ...