The Thai Foreign Ministry issued the statement as the Egyptian capital braced for renewed confrontation on Friday after the Muslim Brotherhood called for a nationwide march after Friday prayers to show anger at a security crackdown on Islamists in which hundreds were killed.
It comes two days after authorities broke up Muslim Brotherhood protest camps in the Egyptian capital with the loss of at least 638 lives.
Egypt is in a state of emergency and police have been authorised to use live ammunition in self-defence.
"Thailand, as a longstanding friend of Egypt, expresses its deep concern at the use of deadly force which lead to several hundred deaths and many more injured. The situation continues to remain fragile, Mr Surapong said. "Thailand calls on all parties to exercise utmost restraint and refrain from all acts of violence."
"The use of violence does not solve any differences. Thailand therefore calls for an immediate end to violence, and for all parties to make the utmost effort to resume an inclusive process of dialogue, which will allow the democratic transition to move forward as soon as possible," the statement said.