The invention provides a novel semiconductive polymer composition with improved smoothness and dispersibility of carbon black when compounding the polymer composition and feasible balance with other properties such as volume resistivity. The semiconductive polymer composition comprises (a) from 30 to 90 wt % of a polymer component, (b) from 10 to 70 wt % of carbon black and the carbon black (b) has a mass pellet strength (MPS) according to ASTM D1937-13 of from 50 to 250 N. The invention further relates to a process for preparing the semiconductive polymer composition comprising the steps of: i) introducing 30-90 wt % of a polymer component as defined above and 0-8 wt % additives in a mixer device and mixing the polymer component and additives at elevated temperature such that a polymer melt is obtained; ii) adding 10-70 wt % of a carbon black as defined above to the polymer melt and further mixing of the polymer melt.