NOVELTY - A controlled-release compound fertilizer (F1) comprises (wt.%): urea (35-65), monoammonium phosphate or triple superphosphate (9-36), potassium chloride or potassium sulfate (3-5), granulated material (1-38), nanometer-grade nanometer modified attapulgite (3-5) and nanometer-grade chitosan capsule agent (1-2). The fertilizer (F1) is prepared by fusing granulation and tumbling encapsulation. The fusing granulation includes fusing, metering and feeding other materials and granulating.    USE - Controlled-release compound fertilizer (F1) for field crop (claimed).    ADVANTAGE - The fertilizer (F1) is friendly to environment and capable of controlling fertilizer effect release speed according to nutrient needs of growing plant at different stages; provides proper amount of nutrients to plant for good growth; and has high fertilizer utilization rate and easily degradable encapsulation material.    DETAILED DESCRIPTION - Controlled-release compound fertilizer (F1) comprises (wt.%): urea (35-65), monoammonium phosphate or triple superphosphate (9-36), potassium chloride or potassium sulfate (3-5), granulated material (1-38), nanometer-grade nanometer modified attapulgite (3-5) and nanometer-grade chitosan capsule agent (1-2). The fertilizer (F1) is prepared by fusing granulation and tumbling encapsulation. The fusing granulation includes fusing, metering and feeding other materials and granulating. The tumbling encapsulation includes conveying granules (98-99 pts. wt.) with obtained controlled-release compound fertilizer into drying wrapping machine; using different-particle varying-velocity technology for uniformly spraying nanometer-grade chitosan capsule agent (1-2 pts. wt.) onto surface of granules through regulating spray amount by electromagnetic valve; processing tumbling encapsulation in encapsulation zone and entering drying zone for drying and cooling by cooler; and metering and packing to obtain controlled-release compound fertilizer of different grain diameters and encapsulation thickness. The fusing process includes pouring granular urea into urea belt conveyer; lifting to urea material chamber by hopper-type lifting machine and conveying into urea fuser by spiral conveyer; fusing urea and making fused urea flow into urea liquid baffle tank; and conveying to first-stage mixing tank by urea liquid pump, where urea solution entered to first-stage mixing tank is 35-65 pts. wt. The metering and feeding of other materials includes:    (A) respectively pouring monoammonium phosphate or triple superphosphate, potassium chloride or potassium sulfate, powdered calcium powder or gypsum powder or anhydrous sodium sulfate or humic acid into belt conveyer;    (B) lifting to individual material chambers by hopper-type lifting machine and installing electronic weighing belt scale on bottom of material chamber for respectively metering monoammonium phosphate or triple superphosphate (9-36 pts. wt.), potassium chloride or potassium sulfate (8-40 pts. wt.) and powdered calcium powder, gypsum powder, anhydrous sodium sulfate or humic acid (1-38); entering into powder heating machine for heating and making heated material flow into powder belt conveyer; and    (C) adding nanometer-grade nanometer modified attapulgite (3-5 pts. wt.) into powder belt conveyer and conveying to first tower top and second mixing tank of granulation process by hopper-type lifting machine and uniformly mixing for granulation.    The granulation process includes applying granulator to uniformly spraying above material into granulated tower; and naturally cooling and curing to obtain granules with controlled-release compound fertilizer.