A simulation model of pine regeneration is presented, based on earlier models and research for natural regeneration of Scots pine in Finland. The model is stochastic, reflecting the unpredictable variation in regeneration results observed in nature. Geographic area, site and stand characteristics and soil preparation affect the simulated regeneration result. The model predicts the amount and quality of seed crop, germination and predation of seeds, and survival and growth of seedlings. The effect of parent trees on seed dispersal, and growth and survival of seedlings is accounted for. At the stand level, the model gives results similar to empirical measurements. The simulation example provided illustrates the effect of density and spatial distribution of the parent tree stand on the regeneration result.