Abstract: The present invention relates to the field of boat trailers, and in particular, to boat trailers with rotatable support structures. The boat trailer includes a front end configured for hitching to a towing vehicle, a rear end, a wheel assembly disposed between the front and rear ends for rolling engagement with the ground and a support frame assembly carried on the wheel assembly. The support frame assembly has a lower base frame portion and an upper carousel frame portion superimposed on, and pivotally connected to, the base frame portion. The carousel frame portion is configured to support a boat thereon. Also provided is a support frame lifting assembly connected to the support frame assembly and the wheel assembly. The support frame lifting assembly is operable to raise at least a portion of the support frame assembly above the wheel assembly so as to permit rotation of the carousel frame portion relative to the base frame portion.