The best answer is "maybe", because the plug in the picture you provided (connected to the AC adapter), looks to be of the kind that would not work with a 5.5x2.1mm jack, but many such power supplies come with plugs that work with both 5.5x2.5mm and 5.5x2.1mm jacks.
See this answer for examples of compatibility, and about the problems with using genders to refer to these kinds of connectors. (The OP and I call that plug "male", while another poster calls it "female". There is enough real-world usage of both labels that neither can be called right or wrong at this point in time. As a result, the overall consensus is to just call them "plugs" and "jacks" instead.)
Also, as another poster noted, double-check the polarity of your power supply. While the consensus is to have the outside of the plug be negative (actually "ground") as shown in your picture, they would not put the picture of it on the device if there were not other devices that expect the outside to be positive.