Mr Eric Holmes and Mrs Anne Prior, who both live in Angmering, have devoted decades to the school as governors and as trustees of the Lavinia Norfolk Centre Trust.
Mr Holmes, who has lived in Angmering since 1969, joined the board of governors in 1976. He has given 46 years of voluntary service to the school, together with many years as a trustee of the associated charity. Mrs Prior joined the board in 1978.
Mr Simon Liley, headteacher and a trustee of the charity, said: "It is incredibly rare to witness such utter dedication and commitment, over such a sustained period of time, to a voluntary position.
"Both the school and the trust feel exceptionally lucky to have benefited from Eric and Anne's support and hard work over the past 46 years. We wish them all the very best for the future."
As both governors and trustees, they have given their time and energy free of charge for the benefit of the students and staff of the school.
As trustees, they have supported fundraising to the tune of hundreds of thousands of pounds which has gone to support the enrichment of hundreds of children's lives.