Partnership is important in a business including the oil palm plantation. As a form of cooperation in business circle, partnership should be exist either directly or indirectly. Moreover, it must be applied in some principles such as mutual need, trust, strengthening, and benefit. Partnership should involve all categories of enterpreneurs-Micro, Small and Medium Enterprises (MSME) actors and large businesses. Article 1 paragraph 13 of Law No. 20/2008 discusses on the Partnership. This topic is interesting due to the presence of the Business Competition Supervisory Commission (Komisi Pengawasan Persaingan Usaha/KPPU) in the supervision of partnerships. This research raises a question, namely what is the legal issue concerning the role of KPPU in supervising the Partnership between Smallholders and Palm Oil Companies. This study analyzes laws and regulations such as (1) Law No. 20/2008 concerning MSME (2), Government Regulation No. 7/2021 concerning Ease, Protection, and Empowerment of Cooperatives and Micro, Small, and Medium Enterprises. Medium. (3) Law No. 39/2014 concerning Plantations, and (4) Law No 11/2020 concerning Job Creation. The researcher also interviewed officer(s) of regional KPPU 1 and ATR-BPN in 4 districts in North Sumatra. The study found that the existence of the KPPU which has function(s) to oversee monopolistic practices and unfair business competition, also oversees the implementation of partnerships. This is regulated in PP 17/2013 which has been revoked by PP No. 7/2021. KPPU conducts supervision in coordination with related institutions such as ATR-BPN in the Plasma core partnership pattern. As conclusion, the existence of the KPPU in supervising the implementation of the Partnership after the fulfillment of the 20% partnership requirement to obtain a HGU permit from an oil palm company is a gap for unfair business competition. As for suggestions, KPPU should conduct intensive coordination with ATR BPN to optimize existing plasma core partnerships.