diff --git a/.changeset/three-cooks-type.md b/.changeset/three-cooks-type.md
new file mode 100644
index 000000000000..1821c286957e
--- /dev/null
+++ b/.changeset/three-cooks-type.md
@@ -0,0 +1,5 @@
+---
+"wrangler": patch
+---
+
+Improve support for package exports conditionals, including "worker" condition
diff --git a/packages/wrangler/src/dev.tsx b/packages/wrangler/src/dev.tsx
index a09e3f3ca791..715555feaf9e 100644
--- a/packages/wrangler/src/dev.tsx
+++ b/packages/wrangler/src/dev.tsx
@@ -374,6 +374,7 @@ function useEsbuild(props: {
         ...(jsxFactory && { jsxFactory }),
         ...(jsxFragment && { jsxFragment }),
         external: ["__STATIC_CONTENT_MANIFEST"],
+        conditions: ["worker", "browser"],
         plugins: [moduleCollector.plugin],
         // TODO: import.meta.url
         watch: {
diff --git a/packages/wrangler/src/publish.ts b/packages/wrangler/src/publish.ts
index 31eb8f1f74a0..79b4478f4d25 100644
--- a/packages/wrangler/src/publish.ts
+++ b/packages/wrangler/src/publish.ts
@@ -99,6 +99,7 @@ export default async function publish(props: Props): Promise<void> {
     format: "esm",
     sourcemap: true,
     metafile: true,
+    conditions: ["worker", "browser"],
     loader: {
       ".js": "jsx",
     },