The objective of this investigation was to develop iced cookies with freeze-dried yellow onion powder (YP) and red onion powder (RP) at composition levels of 0, 1, 3, 5 and 10%. The moisture (13.61%) and crude ash contents (3.43%) of YP was higher than RP, while the crude protein (7.58%) and crude fat contents (0.65%) of RP was higher than YP. Freeze-dried YP showed a higher lightness and yellowness value compared to RP, because of the unique color of the onion. The browning index was lower in YP. The pH of the dough significantly decreased by addition of onion powder, while the density of the dough was significantly increased in RP samples than the others. The iced cookies showed a lower lightness value, and a higher redness value with increase of onion powder contents. Hardness of YP cookies up to 5% and RP cookies up to 3%, were lower compared to the control. With regards to the sensory characteristics, $3{sim}5%$ YP cookies and 3% RP cookies were more acceptable than the others. As a result, the optimal ratio of freeze-dried YP and RP iced cookies were calculated at 5% YP and 3% RP levels.