Operated by Saudi Arabia’s national carrier Saudia, the inaugural flight comes after diplomatic ties between the two countries were normalised last month.
The government has hailed the restored relationship as an opportunity to boost tourist arrivals from the Middle East.
The Tourism and Sports minister will lead a delegation of Thai tourism operators to Saudi Arabia next month.
Meanwhile Saudia will operate three flights per week – on Monday, Wednesday and Friday – on the Riyadh-Bangkok route until March 25.
The summer schedule (March 27 to October 29) will then switch to seven flights per week as follows:
Flight SV 844/845 will fly from Jeddah to Suvarnabhumi airport on Monday, Wednesday, Friday and Sunday, while flight SV846/847 will ply the Jeddah-Riyadh-Suvarnabhumi route on Tuesday, Thursday and Saturday.