NOVELTY - Ammonium phosphate slurry is added into a settling tank (b), nitrogen fertilizer and co-solvent are mixed, maintained to 80-130 degrees C, to obtain co-solvent slurry. Resultant material is granulated, 2-4 times total amount of synthetic ammonia and sulfuric acid is added and preheated to 70-80 degrees C (II). The resultant slurry is fed into granulator of tubular reactor, synthetic ammonia and sulfuric acid are added, mixed, potash fertilizer is added and processed, to obtain semi-finished product (III). The product is dried, sieved and cooled, to obtain water-soluble fertilizer (IV).    USE - Preparation of water-soluble fertilizer containing macroelements (claimed).    ADVANTAGE - The method provides water-soluble fertilizer containing macroelements by simple process with reduced energy consumption.    DETAILED DESCRIPTION - 20-35 wt.% Ammonium phosphate is added into a melt tank, water is added and mixed, to form ammonium phosphate slurry containing moisture content of 25-35%. The resultant slurry is heated to 90-100 degrees C under steam, placed in a settling tank (a), processed for 0.3-2 hours and ammonium phosphate slurry comprising 80% or less water-insoluble material is obtained. 50% Obtained ammonium phosphate slurry is added into a settling tank (b), nitrogen fertilizer is added, mixed, co-solvent is added, mixed, co-solvent slurry (c1) containing moisture content of10-25%, is obtained, the temperature of the settling tank (b) is maintained to 80-130 degrees C for 0.3-2 hours, to obtain co-solvent slurry containing 70% or less water-insoluble material. The resultant material is granulated in a granulator of a tubular reactor, 2-4 times total amount of synthetic ammonia and sulfuric acid is added and preheated to 70-80 degrees C (II). The resultant slurry is fed into granulator of tubular reactor, synthetic ammonia and sulfuric acid are added, mixed, potash fertilizer is added and processed, to obtain semi-finished product containing moisture content of 2-4% (III). The semi-finished product is dried, sieved and cooled, to obtain water-soluble fertilizer containing macroelements having particle size of 2-4.75 mm (IV). Remaining ammonium phosphate slurry with co-solvent is fed with a slurry tank, nitrogen fertilizer is added, stirred, maintained at 80-130 degrees C, to obtain co-solvent slurry (c2), and the slurry (c2) is subjected to steps (I)-(IV). The weight ratio of ammonium phosphate slurry and nitrogen fertilizer is 80:20 or 60:40.