Yes.... if your phone has a USB-C port. Or, if you have a female USB adapter to plug into the Android-type Micro-USB. If you don't have a USB-C port on your phone, yet, there are flash drives with the Micro-USB plug (the current Android-type plug). I have one of these, and it works on my phone. My next phone, which should be here this month, will have the new standard USB-C type port. The other way would be to plug the USB flash drive into your computer, and plug the phone into another USB port on the computer too, and access the data as a folder on your computer. The difference between the current Android, Micro-USB and the new USB-C, is that the Micro needs to be plugged in right-side-up, where the USB-C can be plugged in right-side-up or up-side-down... it doesn't matter.
Images for this Answer
(click to see full-size image)