The action, organised by the National Association of District Hospital Employers and running until Friday, is informational rather than disruptive.
Staff are wearing black T-shirts, buildings are being decorated with flags and posters are going up explaining the situation to patients.
Normal medical services are continuing throughout.
The protest's slogan – "A hospital bed can wait; illness cannot" – reflects concerns that rising costs of energy, medicines and wages, combined with cuts to diagnostic funding, are leaving hospitals unable to carry out tests beyond set limits.
The association's president, Waldemar Malinowski, warned the situation would lengthen waiting times and pose a real threat to patients' health and lives.
Malinowski said at least 40 district hospitals face bankruptcy, and called for the healthcare system to be significantly simplified, describing it as "over-regulated" and increasingly unworkable.
A moment of silence is planned across the country on Wednesday at 11:45 am local time.
The protests come amid a broader funding squeeze.
Poland's National Health Fund (NFZ) faces a shortfall of around PLN 18 billion (EUR 4.25 billion) in its 2026 budget.
(ał)
Source: IAR, PAP