The invention discloses an online bidding method and a system. The system comprises eight subsystems which are basic management system, a business standard management system, an information management system, a bidding process management system, a business support management system, a monitoring management system, a statistic analysis system, and a comprehensive inquiry system. The online bidding system overcomes the problems of low efficiency and high cost, increases the bidding efficiency, reduces the resource consumption, reduces the human factor, and play a positive role of establishing an incorrupt government and preventing corruption. The development mode configured in the invention realizes one-time development for multiple uses, which reduces the cost of system development, unites and standardizes the bidding process and effectively utilizes the related resources.