Conservation is a fundamental function of museums, which serves to preserve the invaluable and irreplaceable cultural property for the future generations. It basically consists of preventive and interventive conservation. In essence, preventive conservation emphasizes on preserving the physical condition of cultural property through the control of environmental parameters, biological activities, and human factors; whereas interventive conservation addresses the treatment needs of individual items and execution of the identified treatment plans. Conservation is a long term commitment which requires the provision of proper care for the cultural property with life-long responsibilities. Inadequate provision of such can result in the loss of cultural property through courses of deterioration, and very often the loss is irrecoverable.
Operating from 13 purpose equipped conservation laboratories, the Conservation Office not only devises, implements and evaluates conservation programmes for museum artifacts and heritage objects, but also conducts technical examination and scientific studies on cultural heritage.  The Office also provides technical assistance and advice on the preservation requirements of museum collections and loan exhibits of the Department.
The artefacts being cared for by the Office vary greatly in nature. They include paintings, paper artifacts, textiles, metals, ceramics, ethnographic objects, wooden artifacts, archaeological finds to outdoor sculptures.
Meanwhile, the Conservation Office provides conservation support for thematic exhibitions and management of some 200,000 collections pertaining to the public museums, Art Promotion Office and Intangible Cultural Heritage Office.