In order to make data collection more convenient, quick and accurate in working site in the existing wireless data acquisition system, one kind of multi-function handheld terminal is designed which combines the wireless and wired data acquisition. The paper adopts Atmega128 of ATMEL as microcontroller, nRF905 of Nordic as data transmission module. It designs power management, liquid-crystal display and data storage circuits. The results of practical test show that the handheld terminal can be applied to all kinds of wireless data acquisition networks, and it has several advantages like easy to carry, large data storage capacity, rich function and low cost.