A modified standard SATA data connector is provided with a power supply circuit. The connector includes male and female data connectors. A male signal interface has seven male data connection pins, consisting of four data, a power supply, and two ground pins, the power supply pin replacing one of three original ground pins and connecting with a power line of a circuit board. A corresponding female signal interface has seven female data connection pins consisting of four data, a power receiving, and two ground pins. While the female and male data connectors are engaged, power can be supplied from the power line of the circuit board to an applied device connected with the female data connector via the power supplying and receiving pins. Thus, the SATA data connector can work without an external SATA power cable, and the volume of the cable can be reduced.