Abstract

As an agricultural country, Indonesia places the plantation sector as one of the main pillars of the national economy. This is reflected in the contribution of PT. Perkebunan Nusantara IV Regional I which produces superior commodities such as palm oil, rubber, and coffee along with various derivative products. In order to maintain competitiveness and ensure business continuity, the company implements an integrated management system as well as key performance indicators (KPIs). Nevertheless, the company still faces challenges in maintaining and improving employee performance. Employee performance is a very important aspect because it is influenced by various factors, including leadership style, work environment, work motivation, and work discipline. Participatory leadership, a conducive and comfortable work environment, adequate motivation levels, and optimal work discipline are believed to be able to encourage increased productivity and overall employee performance at PT. Perkebunan Nusantara IV Regional I. This study applies a quantitative approach and was conducted at PT. Perkebunan Nusantara IV Regional I, Medan City, from March to September 2026. The study population includes all 150 permanent employees. Sampling was conducted using a non-probability sampling method through a purposive sampling approach. The sample size was determined based on the Slovin formula with a 5% error rate, resulting in 109 respondents, of which 30 were used as validity test instruments. The results of the study indicate that, partially and simultaneously, leadership style, work environment, work motivation, and work discipline have a positive and significant effect on employee performance. This is evidenced by the results of the t-test and F-test with a significance level below 0.05. These findings confirm that optimal management of these four variables is crucial in efforts to improve employee performance.