A　mathematical　model　for　simulating　airflow　in　solar　channel　of　the　insulated　Trombe　solar　wall　system　is　proposed.　It　is　assumed　the　glazing　is　isothermal　and　the　solar　heat　absorbed　by　the　wall　is　transferred　to　the　air　in　the　channel　with　a　constant　flux　by　natural　convection.　The　mass,　momentum　and　energy　conservation　equations　are　discretized　and　solved　using　the　finite　difference　control　volume　method.　An　experimental　study　of　solar　chimney　was　used　to　validate　the　proposed　mathematical　model.　The　differences　between　the　predicted　results　of　airflow　rate　in　solar　wall　and　those　of　measurement　data　are　less　than　3.0%　when　the　width　of　solar　wall　is　0.2m　and　wall　temperature　is　lower　than　50°C.　When　the　wall　is　0.3m　wide,　theses　differences　are　lower　than　5.0%　is　the　wall　temperature　less　than　50°C.　Flow　and　temperature　fields　are　produced　and　the　results　are　presented　in　terms　of　temperature　and　velocity　distribution　in　various　parts　of　system.　The　results　show　that　the　solar　heat　gain　and　channel　width　are　two　important　parameters　affecting　the　air　flow　pattern　and　heat　transfer.　Further　experimental　work　is　needed　to　refine　the　model.