The invention relates to a chitosan oligosaccharide silicon-calcium-magnesium multi-element functional fertilizer containing polyglutamic acid. The chitosan oligosaccharide silicon-calcium-magnesium multi-element functional fertilizer containing polyglutamic acid is characterized by being prepared from the following raw materials in parts by weight: 10-20 parts of polyglutamic acid, 15-30 parts ofan amino acid stock solution, 10-30 parts of chitosan oligosaccharide, 10-25 parts of a soil conditioner and 5-15 parts of trace elements, wherein the trace elements are prepared from the following components in parts by weight: 20-50 parts of borax, 5-10 parts of calcium ammoniation nitrate, 5-10 parts of silicon dioxide, 5-10 parts of calcium hydrophosphate, 5-20 parts of magnesium sulfate, 5-10 parts of zinc sulfate, 5-10 parts of manganese sulfate, 5-10 parts of copper sulfate, 0.1-0.5 part of ammonium molybdate, 0.1-0.5 part of titanium sulfate and 3-5 parts of probiotics flora. According to the invention, trace element fertilizers such as boron fertilizer, molybdenum fertilizer, zinc fertilizer, copper fertilizer, manganese fertilizer, magnesium fertilizer, silicon fertilizer, calcium fertilizer, magnesium fertilizer and the like can be supplemented for crops, the drought resistance, cold resistance and lodging resistance of the crops are improved, the metabolism capability of the crops is promoted, and the yield of the crops is increased.