An oil pipe connection device has a base, an oil pipe, a pipe connector and a securing nut. The base has a connection hole and an abutting shoulder. The pipe connector is mounted in the connection hole and has a tapered head, an insertion segment, a pressing collar and an engaging recess. The tapered head abuts with the abutting shoulder. The insertion segment is inserted tightly into an end of the oil pipe. The pressing collar is around the insertion segment and has an inclined guiding surface. The engaging recess is formed between the pressing collar and the insertion segment and holds the end of the oil pipe inside. The securing nut is mounted around the oil pipe, is connected with the connection hole in a threaded manner and has an inclined guiding surface abutting with the inclined guiding surface on the pressing collar.