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）. L_g = 80 nm HEMTs are fabricated with a double-recessed gate process. We focus on their DC and RF responses， including the maximum transconductance （g_{m_max}）， ON-resistance （R_ON）， current-gain cutoff frequency （f_T）， and maximum oscillation frequency （f_max）. The devices have almost same R_ON. The g_{m_max} improves as the whole small recess moves toward the source. However， a small gate to source capacitance （C_gs） and a small drain output conductance （g_ds） lead to the largest f_T， although the whole small gate recess moves toward the drain leads to the smaller g_{m_max}. According to the small-signal modeling， the device with the whole small recess toward drain exhibits an excellent RF characteristics， such as f_T = 372 GHz and f_max = 394 GHz. This result is achieved by paying attention to adjust resistive and capacitive parasitics， which play a key role in high-frequency response.