Abstract: Electricity retail trading systems and methods for coupling a wholesale market are disclosed. In some embodiments, an electricity retail trading system includes a user login module, a trade unit management module, a first display module, a wholesale market trade module, a retail preliminary distribution module, a data acquisition and deviation calculation module, a second display module, a deviation transfer trade module, a third display module, a retail final distribution module, and a fourth display module. In other embodiments, an electricity retail trading method includes the following steps: (a) user login, (b) trade unit management, (c) declaration and clearing of wholesale market trade, (d) retail preliminary distribution of electricity retailer, (e) data acquisition and deviation quantity calculation, (f) declaration and clearing of deviation transfer market trade, and (g) retail final distribution of electricity retailer.