In this work, we investigate the impact of the whole small recess offset on DC and RF characteristics of InP high electron mobility transistors (HEMTs). Lg = 80 nm HEMTs are fabricated with a double-recessed gate process. We focus on their DC and RF responses, including the maximum transconductance (gm_max), ON-resistance (RON), current-gain cutoff frequency (fT), and maximum oscillation frequency (fmax). The devices have almost same RON. The gm_max improves as the whole small recess moves toward the source. However, a small gate to source capacitance (Cgs) and a small drain output conductance (gds) lead to the largest fT, although the whole small gate recess moves toward the drain leads to the smaller gm_max. According to the small-signal modeling, the device with the whole small recess toward drain exhibits an excellent RF characteristics, such as fT = 372 GHz and fmax = 394 GHz. This result is achieved by paying attention to adjust resistive and capacitive parasitics, which play a key role in high-frequency response.