Michael Tordoff-Brown, 49, from Wortley, Leeds, was due to appear in court on Monday for trial accused of sexual offences against a woman but failed to attend.
A West Yorkshire Police spokesman said officers were very concerned for his welfare. It is believed Tordoff-Brown was recently in the Ambleside area of Cumbria.
He is white, about 5ft 10in, with receding, cropped, dark brown hair.
When last seen he was wearing an orange T-shirt and jeans and is believed to be driving a silver Renault Clio, registration VC06XOZ.