Taxi
Take a taxi from Ben-Gurion Airport’s taxi dispatcher station. The cost should be around NIS 160 (approximately $40 U.S. dollars), and the ride should take around 30-40 minutes. Please make sure to use Ben Gurion Airport Authorized taxi through Gett: once you order a taxi through the Gett application you will receive a code, which you will need to show the usher at the authorized taxi line on the second floor exit.
Bus
If you are travelling light, please take the number 5 shuttle to the El Al junction bus stop at airport city, where you can find the #249 bus to Rehovot's central bus station. This is not, however, an express bus and the drive will take approximately 1:15 hours. The cost is about US $3.00. Once at Rehovot's central bus station, there are a multitude of local buses which go to the Weizmann Institute (ask at the information window), or you can take a taxi from the taxi stand directly across the street from the bus station.
Rail
You can also get to the Weizmann Institute by taking the train from the airport. Change at the Tel Aviv Hagana stop for the train to Rehovot. The train station in Rehovot is about a 5-minute walk from the Weizmann Institute.
Ben Gurion Airport Information
For more information, see the web site of the airport in English or in Hebrew.