diff --git a/web/src/components/EventDetailsModal.tsx b/web/src/components/EventDetailsModal.tsx
index 2e653c8..0a836e5 100644
--- a/web/src/components/EventDetailsModal.tsx
+++ b/web/src/components/EventDetailsModal.tsx
@@ -667,10 +667,14 @@ export default function EventDetailsModal({ event, onClose }: EventDetailsModalP
                       type="datetime-local"
                       className="input text-sm"
                       value={editedEvent.attributes.startDate ? new Date(editedEvent.attributes.startDate).toISOString().slice(0, 16) : ''}
-                      onChange={(e) => setEditedEvent({
-                        ...editedEvent,
-                        attributes: { ...editedEvent.attributes, startDate: e.target.value }
-                      })}
+                      onChange={(e) => {
+                        // Convertir la valeur datetime-local en ISO 8601 avec timezone
+                        const isoDate = e.target.value ? new Date(e.target.value).toISOString() : ''
+                        setEditedEvent({
+                          ...editedEvent,
+                          attributes: { ...editedEvent.attributes, startDate: isoDate }
+                        })
+                      }}
                     />
                   ) : (
                     <p className="text-gray-900 dark:text-gray-100">
@@ -688,10 +692,14 @@ export default function EventDetailsModal({ event, onClose }: EventDetailsModalP
                       type="datetime-local"
                       className="input text-sm"
                       value={editedEvent.attributes.endDate ? new Date(editedEvent.attributes.endDate).toISOString().slice(0, 16) : ''}
-                      onChange={(e) => setEditedEvent({
-                        ...editedEvent,
-                        attributes: { ...editedEvent.attributes, endDate: e.target.value }
-                      })}
+                      onChange={(e) => {
+                        // Convertir la valeur datetime-local en ISO 8601 avec timezone
+                        const isoDate = e.target.value ? new Date(e.target.value).toISOString() : ''
+                        setEditedEvent({
+                          ...editedEvent,
+                          attributes: { ...editedEvent.attributes, endDate: isoDate }
+                        })
+                      }}
                     />
                   ) : (
                     <p className="text-gray-900 dark:text-gray-100">
diff --git a/web/src/lib/apiConverters.ts b/web/src/lib/apiConverters.ts
index 6711d1f..7b76837 100644
--- a/web/src/lib/apiConverters.ts
+++ b/web/src/lib/apiConverters.ts
@@ -54,6 +54,24 @@ export const NumberToEnvironment: Record<number, Environment> = {
  * L'API attend des nombres pour les POST/PUT mais renvoie des nombres pour les GET
  */
 export function convertEventForAPI(event: CreateEventRequest): any {
+  // Convertir les dates en format protobuf Timestamp si elles existent
+  const convertDate = (dateStr: string | undefined) => {
+    if (!dateStr) return undefined
+    
+    // Si c'est déjà au format ISO complet, le garder
+    if (dateStr.includes('T') && (dateStr.includes('Z') || dateStr.includes('+'))) {
+      return dateStr
+    }
+    
+    // Sinon, convertir en ISO complet
+    try {
+      return new Date(dateStr).toISOString()
+    } catch (e) {
+      console.error('Error converting date:', dateStr, e)
+      return undefined
+    }
+  }
+
   return {
     ...event,
     attributes: {
@@ -64,6 +82,8 @@ export function convertEventForAPI(event: CreateEventRequest): any {
       environment: event.attributes.environment 
         ? EnvironmentToNumber[event.attributes.environment]
         : undefined,
+      startDate: convertDate(event.attributes.startDate),
+      endDate: convertDate(event.attributes.endDate),
     },
   }
 }