Most commercial banks lack the internal motivation to implement green policies. China's banking performance appraisal system is mainly based on economic indicators, but does not include environmental performance, so it cannot effectively attract the banking industry to support environmental protection projects in practice. In addition, the competition in the banking industry is becoming increasingly fierce. If a commercial bank implements the green credit policy and gives up providing loans to polluting enterprises, other commercial banks may take advantage of it and include customer resources. Without effective supervision mechanism and incentive mechanism, many banks are unwilling to risk losing customers and may even lend to illegal enterprises or projects. The investment risk of green industry is difficult to control and the expected income is unstable. Influenced by many factors, such as policies, market and industry development foundation, there are certain risks in the credit of energy-saving and environmental protection industry projects. Energy-saving and environmental protection projects generally have a long construction period, so it is impossible to enter the investment return period in a short time. Small and medium-sized enterprises and service-oriented enterprises have difficulty in green financing. According to statistics, 90% of enterprises below the scale in China have never had any loan relationship with banks, while 95% of micro-enterprises have never had any loan relationship with banks, while small and medium-sized enterprises often have outstanding environmental problems, and they are generally faced with financing problems in environmental protection technological transformation and pollution control. Green credit is an important means to accelerate the transformation of economic development mode. At present, the challenges and opportunities of national economic transformation coexist. It is very important to implement the green credit policy and give play to the positive role of green credit in changing mode, adjusting structure and promoting environmental protection. First of all, it is necessary to improve the restraint mechanism of "green credit" and establish a system of accountability for illegal environmental lending. By improving relevant legislation and policies, we will establish a mechanism for tracking the whole process of environmental impact of major project loans and compensating pollution accidents. It is suggested that banks should bear legal responsibility for environmental protection and pollution control of loan enterprises. If the loan enterprise causes serious environmental pollution and is unable to pay the pollution cleaning and compensation funds, the bank shall bear joint and several liability. Secondly, establish credit risk prevention policies and risk protection mechanisms for green and emerging industries. We should establish a positive incentive mechanism for institutions that have achieved remarkable results in implementing "green credit". Make full use of fiscal and taxation leverage, establish and improve the system of write-off of bad debts and provision of risk reserves, as well as relevant fiscal and taxation risk compensation policies. In particular, the credit risks arising from the implementation of the "green credit" policy by commercial banks, support for energy conservation and environmental protection, and high-tech development should be given preferential fiscal and tax relief policies, and the tolerance of non-performing loan ratio in energy conservation and environmental protection industries should be appropriately improved. The third is to implement preferential credit incentive policies for green and emerging industries. In terms of loan interest rate, commercial banks should implement differentiated interest rate policies, provide preferential interest rates for enterprises and projects that promote energy conservation and emission reduction and improve the ecological environment, and cultivate the environmental protection industry market in the process of "progress and retreat".