diff --git a/var/spack/repos/builtin/packages/r-affyio/package.py b/var/spack/repos/builtin/packages/r-affyio/package.py
index eb662798558..8d281b7ab26 100644
--- a/var/spack/repos/builtin/packages/r-affyio/package.py
+++ b/var/spack/repos/builtin/packages/r-affyio/package.py
@@ -27,3 +27,4 @@ class RAffyio(RPackage):
 
     depends_on("r@2.6.0:", type=("build", "run"))
     depends_on("r-zlibbioc", type=("build", "run"))
+    depends_on("zlib")