A novel underwater robot water quality data acquisition device includes a casing, a thruster group, an upper cabin, a lower cabin, a buoy cabin, an upper cabin tray, a lower cabin tray, a power supply assembly, a power conditioning module, a data acquisition control module, a water quality sensor assembly, and a wireless Internet of Things (IoT) module. The device can convert the power supply voltage required by each other module through the power management module. The data acquisition control module transmits signals to the water quality sensor assembly in a set timing sequence, performs real-time reading and processing of water quality data fed back from the sensor, and uploads the processed water quality data to the data platform through the wireless IoT module, thereby achieving the display and preservation of water quality data.