diff --git a/ci/appveyor-27.yaml b/ci/appveyor-27.yaml
index 6843c82236a35..bcd9ddee1715e 100644
--- a/ci/appveyor-27.yaml
+++ b/ci/appveyor-27.yaml
@@ -13,7 +13,7 @@ dependencies:
   - matplotlib
   - numexpr
   - numpy=1.12*
-  - openpyxl
+  - openpyxl=2.5.5
   - pytables
   - python=2.7.*
   - pytz
diff --git a/ci/appveyor-36.yaml b/ci/appveyor-36.yaml
index 47b14221bb34b..6230e9b6a1885 100644
--- a/ci/appveyor-36.yaml
+++ b/ci/appveyor-36.yaml
@@ -10,7 +10,7 @@ dependencies:
   - matplotlib
   - numexpr
   - numpy=1.14*
-  - openpyxl
+  - openpyxl=2.5.5
   - pyarrow
   - pytables
   - python-dateutil
diff --git a/ci/circle-27-compat.yaml b/ci/circle-27-compat.yaml
index 5dee6b0c8ed07..84ec7e20fc8f1 100644
--- a/ci/circle-27-compat.yaml
+++ b/ci/circle-27-compat.yaml
@@ -8,7 +8,7 @@ dependencies:
   - jinja2=2.8
   - numexpr=2.4.4 # we test that we correctly don't use an unsupported numexpr
   - numpy=1.9.3
-  - openpyxl
+  - openpyxl=2.5.5
   - psycopg2
   - pytables=3.2.2
   - python-dateutil=2.5.0
diff --git a/ci/circle-36-locale.yaml b/ci/circle-36-locale.yaml
index 59c8818eaef1e..ef97b85406709 100644
--- a/ci/circle-36-locale.yaml
+++ b/ci/circle-36-locale.yaml
@@ -13,7 +13,7 @@ dependencies:
   - nomkl
   - numexpr
   - numpy
-  - openpyxl
+  - openpyxl=2.5.5
   - psycopg2
   - pymysql
   - pytables
diff --git a/ci/circle-36-locale_slow.yaml b/ci/circle-36-locale_slow.yaml
index 7e40bd1a9979e..14b23dd6f3e4c 100644
--- a/ci/circle-36-locale_slow.yaml
+++ b/ci/circle-36-locale_slow.yaml
@@ -14,7 +14,7 @@ dependencies:
   - nomkl
   - numexpr
   - numpy
-  - openpyxl
+  - openpyxl=2.5.5
   - psycopg2
   - pymysql
   - pytables
diff --git a/ci/requirements-optional-conda.txt b/ci/requirements-optional-conda.txt
index 18aac30f04aea..376fdb1e14e3a 100644
--- a/ci/requirements-optional-conda.txt
+++ b/ci/requirements-optional-conda.txt
@@ -12,7 +12,7 @@ lxml
 matplotlib
 nbsphinx
 numexpr
-openpyxl
+openpyxl=2.5.5
 pyarrow
 pymysql
 pytables
diff --git a/ci/requirements-optional-pip.txt b/ci/requirements-optional-pip.txt
index 28dafc43b09c0..2e1bf0ca22bcf 100644
--- a/ci/requirements-optional-pip.txt
+++ b/ci/requirements-optional-pip.txt
@@ -14,7 +14,7 @@ lxml
 matplotlib
 nbsphinx
 numexpr
-openpyxl
+openpyxl=2.5.5
 pyarrow
 pymysql
 tables
@@ -28,4 +28,4 @@ statsmodels
 xarray
 xlrd
 xlsxwriter
-xlwt
\ No newline at end of file
+xlwt
diff --git a/ci/travis-35-osx.yaml b/ci/travis-35-osx.yaml
index 797682bec7208..a36f748ded812 100644
--- a/ci/travis-35-osx.yaml
+++ b/ci/travis-35-osx.yaml
@@ -12,7 +12,7 @@ dependencies:
   - nomkl
   - numexpr
   - numpy=1.10.4
-  - openpyxl
+  - openpyxl=2.5.5
   - pytables
   - python=3.5*
   - pytz
diff --git a/ci/travis-36-doc.yaml b/ci/travis-36-doc.yaml
index 9cbc46d0a70d7..50626088d5bc4 100644
--- a/ci/travis-36-doc.yaml
+++ b/ci/travis-36-doc.yaml
@@ -22,7 +22,7 @@ dependencies:
   - notebook
   - numexpr
   - numpy=1.13*
-  - openpyxl
+  - openpyxl=2.5.5
   - pandoc
   - pyqt
   - pytables
diff --git a/ci/travis-36-slow.yaml b/ci/travis-36-slow.yaml
index 3157ecac3a902..1a7bc53e1b74b 100644
--- a/ci/travis-36-slow.yaml
+++ b/ci/travis-36-slow.yaml
@@ -10,7 +10,7 @@ dependencies:
   - matplotlib
   - numexpr
   - numpy
-  - openpyxl
+  - openpyxl=2.5.5
   - patsy
   - psycopg2
   - pymysql
diff --git a/ci/travis-36.yaml b/ci/travis-36.yaml
index 990ad0fe87dd6..3c9daa5f8b73c 100644
--- a/ci/travis-36.yaml
+++ b/ci/travis-36.yaml
@@ -18,7 +18,7 @@ dependencies:
   - nomkl
   - numexpr
   - numpy
-  - openpyxl
+  - openpyxl=2.5.5
   - psycopg2
   - pyarrow
   - pymysql