There are many customary land conflicts that occur in Indonesia, which are detrimental to the land holders. One of the land conflicts that occurred in Indonesia was found in the Kuala Kapuas PN decision study No 49 / PDT.G / 2018 / PN.KLK where land conflicts occurred between customary land holders and oil palm plantation companies. As for the formulation of the problem in the research as follows, whether Herdeman's land ownership is in accordance with the Law of the Republic of Indonesia Number 5 of 1960 concerning Basic Agrarian Principles, what are the basic considerations used by the judge in the decision of PN KUALA KAPUAS NO 49 / PDT.G / 2018 / PN KLK, how is the legal protection for customary land holders in oil palm plantation land conflicts based on the decision of PN KUALA KAPUAS NO 49 / PDT.G / 2018 / PN KLK. As for the purpose of the study to determine the suitability of land ownership by Herdeman with the Law of the Republic of Indonesia Number 5 of 1960 concerning Basic Agrarian Principles, knowing the basic considerations used by judges in the decision of PN KUALA KAPUAS NO 49 / PDT.G / 2018 / PN KLK, knowing Legal Protection for Customary Land Holders in Conflict of Oil Palm Plantation Land in the decision of PN KUALA KAPUAS NO 49 / PDT.G / 2018 / PN KLK. The research method taken is juridical normative, namely legal research by examining library materials or secondary data, from the results of research that the researcher examines the ownership of land owned by Herdeman when viewed from the Law of the Republic of Indonesia Number 5 of 1960 concerning the Basic Regulations Agraria is still not suitable because there has not been any hatching of conversion or land registration, the basis for consideration used by the judge in the Kuala Kapuas District Court decision No 49 / PDT.G / 2018 / PN.KLK using evidence of letters, witnesses, existing regulations, legal protection in the study Kuala Kapuas District Court decision No 49 / PDT.G / 2018 / PN.KLK was good enough because almost part of the lawsuit was granted.