This　study　evaluated　the　working　memory　performance　of　18　patients　experiencing　their　first　onset　of　mild　depression　without　treatment　and　18　healthy　matched　controls.　The　results　demonstrated　that　working　memory　impairment　in　patients　with　mild　depression　occurred　when　memorizing　the　position　of　a　picture　but　not　when　memorizing　the　pictures　themselves.　There　was　no　significant　difference　between　the　two　groups　in　the　emotional　impact　on　the　working　memory,　indicating　that　the　attenuation　of　spatial　working　memory　was　not　affected　by　negative　emotion;　however,　cognitive　control　selectively　affected　spatial　working　memory.　In　addition,　the　accuracy　of　spatial　working　memory　in　the　depressed　patients　was　not　significantly　reduced,　but　the　reaction　time　was　significantly　extended　compared　with　the　healthy　controls.　This　finding　indicated　that　there　was　no　damage　to　memory　encoding　and　function　maintenance　in　the　patients　but　rather　only　impaired　memory　retrieval,　suggesting　that　the　extent　of　damage　to　the　working　memory　system　and　cognitive　control　abilities　was　associated　with　the　corresponding　depressive　symptoms.　The　development　of　mild　to　severe　depressive　symptoms　may　be　accompanied　by　spatial　working　memory　damage　from　the　impaired　memory　retrieval　function　extending　to　memory　encoding　and　memory　retention　impairments.　In　addition,　the　impaired　cognitive　control　began　with　an　inadequate　capacity　to　automatically　process　internal　negative　emotions　and　further　extended　to　impairment　of　the　ability　to　regulate　and　suppress　external　emotions.　The　results　of　the　mood-congruent　study　showed　that　the　memory　of　patients　with　mild　symptoms　of　depression　was　associated　with　a　mood-congruent　memory　effect,　demonstrating　that　mood-congruent　memory　was　a　typical　feature　of　depression,　regardless　of　the　severity　of　depression.　This　study　provided　important　information　for　understanding　the　development　of　cognitive　dysfunction.