It happened about 1:30 a.m. Wednesday on Coastal Highway in Rehoboth Beach.
Police say a trooper on patrol saw a bicyclist traveling north without a headlight and weaving in and out of the travel lane while texting.
Authorities say the trooper pulled the marked cruiser onto the shoulder ahead of the bicyclist and got out to order him to stop.
Police say the bicyclist rode past the trooper and crashed into the rear of the cruiser.
Troopers say the bicyclist, 22-year-old Huseyin Engin Uysal of Rehoboth Beach, was not hurt.