Dear sir, is there train to HK airport from kowloon railway station..

For Kowloon Railway Station, do you refer to the Kowloon Station of MTR or the Hung Hom Station in Kowloon District.
If you refer to the first one, you can take the airport express to reach Kowloon Station directly.
If you refer to the second one, you can take the airport shuttle bus line A21 to reach its terminal at Hung Hom Station. Get off the bus, you can see the Hung Hom Railway Station.