Arsyad Husein Harahap, Nirm. 01.04.18.007, Effectiveness of Pest Control Oryctes rhinoceros By Manual And Mechanical Spray On Oil Palm Plants (Elaeis guineensis Jacq.) At PT. Socfindo Kebun Bangun Bandar, Serdang Bedagai Regency. This study aims to assess the effectiveness of pest control Oryctes rhinoceros based on the level of attack, land area, labor and control costs at PT. Socfindo Kebun Bangun Bandar. The assessment method used is descriptive quantitative conducted by collecting data from the estate office, field and direct interviews. The implementation of the study was carried out at PT. Socfindo Kebun Bangun Bandar, Dolok Masihul District, Serdang Bedagai Regency. The study was conducted from February to July 2022. The statistical analysis method used to determine the effectiveness of manual and mechanical sprays was using tables, graphs and the Independent Sample t-Test. The results of tables and graphs show that the use of mechanical spray is more effective with an attack percentage of 0.64% but the results of the Independent Sample t-Test test that there is no effect between manual and mechanical spray. The factors that influence the control of Oryctes rhinoceros pests are land area, labor and control costs.