Arriving at Mahidol University
Registered metered taxi service is available at the airport with an extra 50 BAHT charge and the taxi queue is located just outside the arrival area. It should cost around 400 to 500 BAHT (10 to 12 USD) to get to Salaya Campus. Please note that "registered meter-taxi service" is different from "airport taxi". The latter belongs to the airport and costs more than the metered taxi (or about 800 to 900 BAHT,or 18 to 20 USD).
If you are looking for the most economical choice, take the airport bus. The last stop is at Rajadamnoen Road and costs 60 BAHT (1.50 USD). Then get off the bus and take a metered taxi. Tell the driver that you would like to go to Mahidol University, Salaya Campus. The approximate cost from Rajadamnoen Road to the Salaya Campus should be between 120 to 150 BAHT (4 to 5 USD).