Low-energy electron collisions with the X3Σg- ground state and a1Δg and b1Σg+, the Herzberg states (c1Σu-, A'3Δu, and A3Σu+), and B3Σu- excited states of the O2 molecules are studied using the fixed-nucleus R-matrix method. Integral elastic scattering and electronic excitation cross sections from the X3Σg- ground state overall agree well with the available experimental and theoretical results. The electronic (de-)excitation cross sections for the electron impact with the Herzberg states and the B3Σu- state are reported. The value of elastic cross sections for the six excited states decreases with the increment of electron energy, except for the resonance peaks. As the case of excitation from the X3Σg- ground state, the O2- 2Πu resonance makes a dominant contribution to the (de-)excitation cross sections from the a1Δg, b1Σg+, and the Herzberg states. The magnitude of the de-excitation cross sections at the location of the 2Πu resonance from the Herzberg states to the ground state is about 2 to 8 times those of the excitation cross sections for the corresponding excitation transitions. These results should be significant for models of oxygen plasma and the dynamics of the Herzberg states of molecular oxygen in the earth's atmosphere.