diff --git a/src/mito2/src/config.rs b/src/mito2/src/config.rs
index 66d688a39f53..b4d77d145707 100644
--- a/src/mito2/src/config.rs
+++ b/src/mito2/src/config.rs
@@ -92,7 +92,7 @@ impl MitoConfig {
         // Sanitize worker num.
         let num_workers_before = self.num_workers;
         if self.num_workers == 0 {
-            self.num_workers = num_cpus::get() / 2;
+            self.num_workers = (num_cpus::get() / 2).max(1);
         }
         if num_workers_before != self.num_workers {
             warn!(