The bright green Balkan reptile, which is not dangerous, said goodbye to temperatures of 26C (78.8F) when it travelled over 2,000 miles from Kos to a much cooler Bridgend.
After discovering him in their belongs on their return home to Laleston on 6 June, the holidaymaker called the RSPCA.
The lizard, around 20cm long, or 8 inches, had shed its tail – a common defence mechanism for the species – but apart from that, he was in good condition, despite the journey.
The animal is now being cared for at Silent World, which specialises in exotic creatures.
RSPCA inspector Nic de Celis said: “We’re really grateful to the callers, who contacted us and safely confined the lizard in their utility room before we came and made the rescue.
“As a stowaway in a suitcase from Kos to Bridgend for many hours, and with temperatures falling from a high of 26C to 15C, this was some ordeal for the reptile.
“Fortunately, this lizard is now at a specialist centre in Pembrokeshire for boarding and care and is doing well. It is anticipated it will now live there, in safe and appropriate conditions.”
Russ and Ginny Spenceley, who run Silent World, added: “He’s quite friendly, went straight into a vivarium with us and is eating locusts directly from our hands.
“This lizard will join our other exotic species kept at our specialist facilities.”