1987年由基督教興學會有限公司開辦，校訓係「明道律己，忠主善羣」。辦學宗旨係給予學生靈、德、智、體、羣、美嘅全人教育。該校喺1998年獲教育署（依家叫教育局）批准繼續以英文作為授課語言，當年係西貢區唯一一間資助英文中學。但係教學語言微調實施之後，區內已經有其他中學全面用英文授課。迦密主恩中學有四個社：Matthew（馬太）、Mark（馬可）、Luke（路加）、John（約翰），以聖經新約四福音嘅四個作者命名。學校喺1987年9月1號創立開課嗰陣，因為附近嘅寶林邨未入夥，所以係無交通工具途經嘅，午膳就要向快餐店訂飯盒，學生同教職員出入都好睏難，得校方安排嘅上下晝各一班旅遊車接送，經運輸署協調之後，九龍巴士93A線提早兩個月，喺1987年9月7號開辦。
Founded in 1987 by Christian Society Limited with the motto of "Enlightened Self-discipline, Loyalty to the Lord and Good Men". The purpose of the school is to provide students with a whole-person education of spirituality, morality, intelligence, physique, community and beauty. In 1998, the school was approved by the Education Department (now known as the Education Bureau) to continue to use English as the medium of instruction, and was the only aided English secondary school in Sai Kung District at that time. However, after the implementation of the fine-tuning of the medium of instruction, other secondary schools in the district have been fully taught in English. Carmel Lord's Grace School has four clubs: Matthew, Mark, Luke, and John, named after the four authors of the four New Testament gospels of the Bible. When the school was founded on September 1, 1987, because the nearby Po Lam Village was not occupied, so there was no means of transportation, and lunch had to be ordered from a fast food restaurant, and it was very difficult for students and staff to enter and exit, so the school arranged a tour bus in the morning and afternoon, and after the coordination of the Transport Department, the Kowloon Bus Route 93A was opened two months earlier on September 7, 1987.