diff --git a/subworkflow/filtering.nf b/subworkflow/filtering.nf
new file mode 100644
index 0000000..4921f1a
--- /dev/null
+++ b/subworkflow/filtering.nf
@@ -0,0 +1,21 @@
+process FILTERING {
+
+    input:
+        val(datadir)
+        val(publishdir)
+        val(target)
+        val(length)
+        val(qcscore)
+
+    output:
+        val(datadir)
+
+    script:
+
+        """
+        fastqc -o ${publishdir} ${datadir}/${target}/${target}.fastq.gz
+        gunzip -c ${datadir}.fastq.gz| chopper -q ${qcscore} --minlength ${length} -t 30 | gzip > ${publishdir}/${datadir}_filtered.fastq.gz
+        fastqc -o ${publishdir} ${publishdir}/${datadir}_filtered.fastq.gz
+        """
+
+}