Method for monitoring, sampling and control of a plant for producing wood pellets, the method comprising: - receiving chip raw material in a chip dryer in which moisture is removed from the material, wherein the chip dryer is controlled by temperature and in which chip dryer moisture content in the chips is measured continuously with capacity sensors and adjusted if necessary by adding moisture, - from the chip dryer further feeding the chips to a hammer mill in which the chips are milled further compared with the chip raw material, - from the hammer mill further feeding the chips in direction to a mixer passing before the mixer a dosing device for additives in which additives may be added, - in the subsequent mixer the chips and additive are mixed, wherein in the mixer the moisture content may be adjusted by a humidity adjusting device, - from the mixer further feeding the chips to an intermediate storage, - from the intermediate storage feeding the chips by a dosing screw for a pellet press to a pellet press in which wood pellets are produced, - moving these finalized wood pellets to a pellet cooling device, - after the cooling sifting the finalized wood pellets in a pellet-sieving device, - after the sifting automatic sampling of the wood pellets by automatically filling a sample cylinder with wood pellets, and - analyzing the sample regarding moisture content by using one or more microwave sensors, regarding temperature by using a temperature sensor and regarding bulk density by that the sample cylinder is arranged at a measuring cell for measuring the volume weight of the sample, wherein the sampling, control measurement of the sample regarding predefined control parameters, evaluation of the test results, possible adjustment of appropriate control parameter based on the test results, are performed according to predetermined frequency and fully automated during operation of the plant, to control the quality level of the wood pellets. - receiving chip raw material in a chip dryer in which moisture is removed from the material, wherein the chip dryer is controlled by temperature and in which chip dryer moisture content in the chips is measured continuously with capacity sensors and adjusted if necessary by adding moisture, - from the chip dryer further feeding the chips to a hammer mill in which the chips are milled further compared with the chip raw material, - from the hammer mill further feeding the chips in direction to a mixer passing before the mixer a dosing device for additives in which additives may be added, - in the subsequent mixer the chips and additive are mixed, wherein in the mixer the moisture content may be adjusted by a humidity adjusting device, - from the mixer further feeding the chips to an intermediate storage, - from the intermediate storage feeding the chips by a dosing screw for a pellet press to a pellet press in which wood pellets are produced, - moving these finalized wood pellets to a pellet cooling device, - after the cooling sifting the finalized wood pellets in a pellet-sieving device, - after the sifting automatic sampling of the wood pellets by automatically filling a sample cylinder with wood pellets, and - analyzing the sample regarding moisture content by using one or more microwave sensors, regarding temperature by using a temperature sensor and regarding bulk density by that the sample cylinder is arranged at a measuring cell for measuring the volume weight of the sample, wherein the sampling, control measurement of the sample regarding predefined control parameters, evaluation of the test results, possible adjustment of appropriate control parameter based on the test results, are performed according to predetermined frequency and fully automated during operation of the plant, to control the quality level of the wood pellets.