The invention provides a network online invoice making method. Based on internet and computer technology, the method provides comprehensive real-time management services for the links of purchase, making, use, inquiry, data application and the like of an invoice of a taxpayer. The method comprises the following steps of: realizing the authentication of a taxpayer identity by using a digital certificate; ensuring the transmission security of invoice data on the internet by using an HTTPS encryption protocol; establishing a security channel between a user and a backstage server; realizing bidirectional data security transmission by encryption technology; generating an invoice security code used for verifying the authenticity and the completeness of invoice face value information by invoice anti-counterfeiting technology. An online invoice making key is a medium for the digital certificate, a face value anti-counterfeiting algorithm and secure storage, and finishes data encryption, data decryption, digital signature, data verification and the like. Therefore, the problems of false invoice, writing false invoice, making an invoice excluding income, filling and making non-standard invoice, declaration data distortion and the like are solved fundamentally.