diff --git a/portfolios/filters.py b/portfolios/filters.py
new file mode 100644
index 0000000..197faf5
--- /dev/null
+++ b/portfolios/filters.py
@@ -0,0 +1,17 @@
+from django_filters import rest_framework as filters
+from django.db.models import Q
+from .models import Portfolio
+
+class PortfolioFilter(filters.FilterSet):
+    category = filters.CharFilter(method='filter_category')
+
+    def filter_category(self, queryset, name, value):
+        categories = value.split(',')
+        q = Q()
+        for c in categories:
+            q |= Q(category__contains=[c])
+        return queryset.filter(q)
+
+    class Meta:
+        model = Portfolio
+        fields = ['category']