Phuket Marine Office Chief Nachaphong Pranit explained that the number of people using tour boats and ferries to and from Phuket had increased dramatically since the long weekend began on Thursday.
The inspections were aimed at ensuring the safety of tourists, Mr Nachapong said.
Officers conducted checks to make sure that passenger capacity limits were not exceeded, that boats were properly registered and boat operators were fully licenced, and that appropriate safety equipment was on board and in full working order.
Captains and crews were reminded to ensure they check weather reports and wave conditions regularly, and heeded all communications by marine officials, especially regarding safety measures.
The inspections found no violations of any maritime regulations, regarding safety or otherwise, Mr Nachaphong said.
People can report any maritime accidents or safety concerns or incidents by calling the Marine Department 24-hour hotline 1199, Mr Nachapong said.