diff --git a/packages/cozy-pouch-link/src/mango.js b/packages/cozy-pouch-link/src/mango.js
index f6fb351e3..360a031b0 100644
--- a/packages/cozy-pouch-link/src/mango.js
+++ b/packages/cozy-pouch-link/src/mango.js
@@ -53,12 +53,25 @@ export const getIndexNameFromFields = (fields, partialFilter) => {
   const indexName = `by_${fields.join('_and_')}`
 
   if (partialFilter) {
-    return `${indexName}_filter_(${makeKeyFromPartialFilter(partialFilter)})`
+    const filterKey = makeKeyFromPartialFilter(partialFilter)
+    return sanitizeIndexName(`${indexName}_filter_(${filterKey})`)
   }
 
   return indexName
 }
 
+/**
+ * Sanitize an index name to remove characters that are not compatible with
+ * CouchDB design document naming conventions (e.g. "/" breaks CouchDB > 3.3.3)
+ * https://github.com/linagora/cozy-client/issues/1667
+ *
+ * @param {string} name - The index name to sanitize
+ * @returns {string} The sanitized index name
+ */
+const sanitizeIndexName = name => {
+  return name.replace(/%/g, '%25').replace(/\//g, '%2F')
+}
+
 /**
  * @function
  * @description Compute fields that should be indexed for a mango
diff --git a/packages/cozy-stack-client/src/mangoIndex.js b/packages/cozy-stack-client/src/mangoIndex.js
index c75be3e64..661dbd72d 100644
--- a/packages/cozy-stack-client/src/mangoIndex.js
+++ b/packages/cozy-stack-client/src/mangoIndex.js
@@ -98,12 +98,25 @@ export const getIndexNameFromFields = (fields, partialFilter) => {
   const indexName = `by_${fields.join('_and_')}`
 
   if (partialFilter) {
-    return `${indexName}_filter_(${makeKeyFromPartialFilter(partialFilter)})`
+    const filterKey = makeKeyFromPartialFilter(partialFilter)
+    return sanitizeIndexName(`${indexName}_filter_(${filterKey})`)
   }
 
   return indexName
 }
 
+/**
+ * Sanitize an index name to remove characters that are not compatible with
+ * CouchDB design document naming conventions (e.g. "/" breaks CouchDB > 3.3.3)
+ * https://github.com/linagora/cozy-client/issues/1667
+ *
+ * @param {string} name - The index name to sanitize
+ * @returns {string} The sanitized index name
+ */
+const sanitizeIndexName = name => {
+  return name.replace(/%/g, '%25').replace(/\//g, '%2F')
+}
+
 /**
  * Transform sort into Array
  *
diff --git a/packages/cozy-stack-client/src/mangoIndex.spec.js b/packages/cozy-stack-client/src/mangoIndex.spec.js
index 0ded7cd07..d523a15aa 100644
--- a/packages/cozy-stack-client/src/mangoIndex.spec.js
+++ b/packages/cozy-stack-client/src/mangoIndex.spec.js
@@ -255,6 +255,34 @@ describe('getIndexNameFromFields', () => {
     )
   })
 
+  it('should sanitize slash characters from index name', () => {
+    const partialFilter = {
+      _id: {
+        $nin: ['io.cozy.files.trash-dir', 'io.cozy.files.shared-drives-dir']
+      },
+      path: {
+        $or: [{ $exists: false }, { $nin: ['/Settings'] }]
+      }
+    }
+
+    const indexName = getIndexNameFromFields(fields, partialFilter)
+    expect(indexName).not.toContain('/')
+    expect(indexName).toContain('%2FSettings')
+  })
+
+  it('should produce different index names for values with and without slash', () => {
+    const withSlash = {
+      path: { $nin: ['/Settings'] }
+    }
+    const withoutSlash = {
+      path: { $nin: ['Settings'] }
+    }
+
+    const nameWithSlash = getIndexNameFromFields(fields, withSlash)
+    const nameWithoutSlash = getIndexNameFromFields(fields, withoutSlash)
+    expect(nameWithSlash).not.toEqual(nameWithoutSlash)
+  })
+
   it('should return index fields with partial filter with $nor inside sub condition', () => {
     const partialFilter = {
       $nor: [