At least 90% of final year students at Cardiff, Swansea and Bangor said they were happy with their university experience.
Aberystwyth and Cardiff Metropolitan both scored 83% in the 11th National Student Survey.
Elsewhere, Glyndwr scored 80% while University of South Wales and Trinity St David both had 79% satisfaction.
More than 300,000 people were surveyed at universities and colleges around the UK were asked about a wide range of subjects.
The results shows overall satisfaction has remained steady, and there were particular gains in the areas of learning resources and satisfaction with the students' union.
There have also been improvements in teaching, assessment and feedback, academic support, organisation and management, personal development and NHS practice placements.
In all categories relating to the academic student experience, satisfaction has either improved or stayed the same since 2014.
Dr David Blaney, chief executive of Higher Education Funding Council for Wales, said: "The strong performance of the Welsh HE [higher education] sector reflects the continuing work to enhance the student experience and provide students with an excellent learning environment.
Three Welsh universities are among the top places in the UK for student satisfaction, a new survey shows.