The susceptibility of some onion varieties namely, Giza 20, Giza 6 Mohassan and Shandweel 1 to onion thrips and onion maggot infestation was tested during two successive onion growing seasons, 97/98 and 98/99.  It was found that all onion varieties were liable to the infestation by Thrips tabaci and Delia alliaria.  The onion variety Shandweel 1 demonstrated the highest infestation records, meanwhile Giza 20 variety showed the least parameter.  On the other hand, the rate of infestation for onion maggot varied greatly differences in the susceptibility for onion varieties.  Giza 6 Mohassan variety harboured the highest infestation rates expressed as percentage of infestation while Giza 20 showed less susceptible.  When the total bulb yield/fed., it was found that Giza 20 produced the highest yield weight figure followed by Shandsweel 1 and Giza 6 Mohassan onion varieties respectively.