Emergency services were called to the junction of Otley Old Road and Tinshill Road in Cookridge shortly before 1.15pm today.
Drivers are being advised that the section of road around the junction is currently blocked, so they should take care if driving in the area.
A police spokesman said the cyclist, a man in his 40s, had been taken to hospital for treatment.
His injuries were described as serious and potentially life-threatening.
The driver of the vehicle stopped at the scene and is being spoken to by officers as they seek to build up a clearer picture of the circumstances of the crash.