Metallophthalocyanines　(MPc)　exhibit,　among　many　useful　properties,　the　ability　to　protect　sensors　against　short,　intense　pulse　deleterious　to　efficient　sensor　operation.　For　the　successful　application　of　this　optical　limiting　property,　an　important　issue　is　the　incorporation　of　MPc　molecules　in　a　matrix　to　fabricate　a　solid　state　system.　We　report　here　the　study　of　different　concentrations　of　aromatic　oxygen　palladium　phthalocyanine　(ArOPdPc)　encapsulated　in　silica　xerogel　obtained　by　the　sol-gel　technique.　The　resulted　composites　were　transparent　and　homogeneous　with　the　required　optical　limiting　properties.　The　trapping　effect　was　confirmed　by　the　characteristic　absorption　bands　of　ArOPcPd　in　the　UV-Vis　spectra.　The　optical　limiting　properties　of　the　composites　were　measured　at　532　nm　with　8　ns　pulses.　The　results　showed　that　the　composites　had　obviously　optical　limiting　effect,　owing　to　the　existing　of　large　amount　of　monomers　and　the　introduction　of　palladium　atom　in　the　cavity　of　phthalocyanine　ring.　(C)　2002　Elsevier　Science　B.V.　All　rights　reserved.