2 KMnO4 (aq) + 3 MnSO4 (aq) + 2 H2O (l) → 5 MnO2 (s) + K2SO4 (aq) + 2 H2SO4 (aq)
This is an oxidation-reduction (redox) reaction:
3 MnII - 6 e- → 3 MnIV (oxidation)
2 MnVII + 6 e- → 2 MnIV (reduction)
MnSO4 is a reducing agent, KMnO4 is an oxidizing agent (synproportionation (comproportionation)).