(40 min) from Munich main station S1 or train (20 min) to Freising, then bus 638 to Weihenstephan or walk (20 min).
And from the airport by taxi (15 min). Alternatively, take bus 635 to Freising station (10 min) and the bus 638 to Weihenstephan.
If you wish to travel by car, you can calculate a route planner with a unique route. Enter your personal starting address in the appropriate field. The destination address is automatically adopted.