The electricity load scheduling problem in a household with roof-top photovoltaic (PV) system can efficiently reduce customers’ payments. Compared with previous works in which common flat rate (CFR) has been used, this paper study the case where the time-of-use pricing (TOUP) is adopt. Two conditional equations are constructed for different gains of customers. This is caused by different power direction between the household and the main grid. The two conditional gains equations for the customer are transformed into linear equations by introducing auxiliary variables and linear expression techniques. As a result, established mathematical model to maximize gains for customer is transformed into a mixed integer linear programing (MILP) problem. Thus the resulting MILP model can be easily solved by existing powerful commercial solver. The adjustable and rating power consumption property of appliances are both considered. There are two different mathematic models for them respectively. The impact of reduction of the maximum exchange power between the household and the main grid on gains of the customer, gains of the main grid, load demand during off-peak time and energy exported to the main grid is also studied. The validity and feasibility of the proposed model is illustrated by the case studies.