A connection structure between an aluminum alloy drill pipe body and a steel joint of an aluminum alloy drill pipe includes a first joint at an end of the aluminum alloy pipe body and a steel second joint; wherein the first joint includes a first external threaded section and a second external threaded section provided from outside to inside thereof, and a major diameter of the first external threaded section is smaller than that of the second external threaded section; and wherein the second joint includes a first internal threaded section which is able to be fitted with the first external threaded section and a second internal threaded section which is able to be fitted with the second external threaded section, and a pitch diameter of the second external threaded section is larger than that of the second internal threaded section.