Using transient capacitance spectroscopy, we studied defect energy levels and their annealing behavior in boron-doped silicon of various resistivities irradiated with 1-MeV electrons at room temperature. Three levels located at ${E}_{v}+0.23$, ${E}_{v}+0.38$, and ${E}_{c}\ensuremath{-}0.27$ eV consistently appear in various samples, showing they are characteristic defects in boron-doped silicon. Many properties of the ${E}_{v}+0.23$-eV level and the divacancy are the same, according to the present study and others. We correlated the ${E}_{v}+0.38$-eV level to the vacancy-oxygen-carbon complex recently identified by Lee and Corbett using the EPR technique. The ${E}_{c}\ensuremath{-}0.27$-eV level could arise from an interstitial defect of oxygen and boron; and a new level at ${E}_{v}+0.30$ eV arising upon its disappearance could be a vacancy defect trapping an oxygen atom and a boron. Several additional defect levels are reported.