To apply for a South Korean visa as a Filipino citizen, you typically need to show proof of sufficient funds to cover your expenses during your stay. The exact amount required may vary depending on the type of visa you are applying for and your specific circumstances. It is recommended to have at least around 70,000-80,000 Philippine pesos (approximately 1,400-1,600 USD) in your bank account as a reference. However, it is always best to check with the South Korean embassy or consulate in the Philippines for the most up-to-date and accurate information on visa requirements.