The National Association of Teachers of RE (NATRE) surveyed over 500 primary teachers from across the country.
A quarter of teachers reported that colleagues within their schools have a lack of confidence in teaching RE, both in terms of what to teach, but also how to teach RE.
Ben Wood, NATRE Chair said: "It is undoubtedly disheartening to hear such news, but not surprising. We know there are wonderful examples of high quality RE going on in primary schools, with excellent teachers who use the subject to help their students grow up with a broad understanding of and open-minded attitude to the world and the people who inhabit it.
"But we also know that there are too many students who don't get the quality of RE they deserve and are entitled to receive. This not only risks students' own futures but also the future cohesion of our wonderfully diverse country."
Wood added that the concerns are not limited to primary education.
He explained: "A similar account emerges about secondary schools.
"It angers me that young people are being denied an important part of their education, that colleagues are losing their jobs, that the superb examples of high quality RE in some schools are not replicated in the school down the road and that government that speaks warm words about the value and importance of RE, but then does little to correct the situation."
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