1. Two-party system is relatively expensive to operate compared to one party system.
2. It may lead to the division of states into different political functions.
3. The presence of an opposition party could lead to political instability.
4. It does not promote national unity due to the power tussle that exists.
5. It promotes unhealthy party rivalry, which often time leads to the victimization of some prominent political heavy weights.
6. It encourages electoral malpractices.