The invention discloses arginine-substituted phthalocyanine derivatives and a synthesis method thereof, and application of the arginine-substituted phthalocyanine derivatives in photodynamic therapeutics. The structure of the arginine-substituted phthalocyanine derivatives is disclosed as the following formula in the specification. The synthesis method of the arginine-substituted phthalocyanine derivatives is simple, and does not need any toxic methylation reagent; and the arginine-substituted phthalocyanine derivatives are positively charged under physiological conditions, have the advantages of high active oxygen generation capacity, favorable photosensitive antineoplastic activity and low dark toxicity, and thus, have favorable application prospects in photodynamic therapeutics.