A 2.4-GHz CMOS on-off keying (OOK) transmitter is developed for applications that require high data rate over 10Mbps in the area of wireless body area network (WBAN) and medical implant communication service (MICS). A novel analog pulse-shaping circuit for reducing power consumption and circuit complexity is employed for the OOK transmitter. Fabricated in 0.13µm CMOS, the transmitter core excluding the 50 ohm driving buffer dissipates 0.95mW from 1.2-V supply. Measurement shows that it can support the data rate up to 22Mbps. With the pulse-shaping capability enabled, the transmitter output spectrum shows successful suppression of the sidelobe power below -42dBc at 100MHz offset from the center frequency.