Oil palm harvesting activity is mostly done by 'human power' manual handling, therefore the activity may cause work safety and health problems.This research is deal with anthropometry, motion study and biomechanic to find out the risk of manual handling and to develop ergonomic assessment model of oil palm harvesting. This model was designed in the aims to find out better work motion, good procedure and better design of harvesting tool, so the manual harvesting can be done in more safe, efficient and productive. The formula for the appropriate distance between harvester's position and the tree and the length of egrek show that oil palm harvesting for more than 16 m bunches's height is not safe with 'egrek'. Critical load for neck, shoulder and forearm are 21.85 N, 1091.96 N and 1634.31 N. Ergonomic risk assesment's tool of oil palm manual harvesting was designed with the parameter: appropriate distance (dt), the length of egrek (lp), critical range of motion (CRM) and critical load (CL) for neck, shoulder and forearm.