The　650nm　oxide-confined　RCLEDs　(resonant-cavity　light-emitting　diodes)　have　been　fabricated　with　different　oxide　aperture　diameters.　The　oxide　apertures,　which　could　apply　confinement　of　both　the　carrier　distribution　and　the　optical　field,　are　created　by　lateral　selective　wet　oxidation　of　AlAs　layer　in　the　p-DBR　(distributed　Bragg　reflectors).　All　samples　have　the　same　diameter　80　mu　m　of　the　emission　window　defined　by　the　circular　electrodes,　while　their　current　apertures　are　defined　by　the　oxidation　apertures　ranged　from　90　mu　m　to　130　mu　m,　larger　than　the　emission　window.　The　maximum　optical　power　is　1.909mW.　The　electrical　and　optical　properties　are　systematically　discussed　for　different　oxide　apertures.　The　greater　voltage　at　20mA　is　attained　for　smaller　oxide-aperture　devices　as　smaller　oxide-aperture　devices　have　greater　series　resistance　due　to　the　oxide　layer.　The　maximum　output　power　is　reached　rapidly　for　smaller　oxide-aperture　devices　since　smaller　oxide-aperture　devices　have　larger　current　density　at　the　same　current.　The　maximum　output　power　of　smaller　oxide-aperture　devices　is　lower　than　that　of　larger　oxide-aperture　devices.　It　is　because　that　larger　current　density　and　greater　series　resistance　could　lead　to　greater　Joule　heat,　which　results　in　more　injected　electrons　relax　their　energy　by　the　way　of　nonradiation.