diff --git a/CHANGELOG.md b/CHANGELOG.md
index 760d5b653..647f1c7bc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -78,6 +78,7 @@ at anytime.
   * Removed claim information from lbry file internals
   * Removed `auto_re_reflect` setting from the conf file, use the `reflect_uploads` setting instead
   * Removed `include_tip_info` argument from `transaction_list`, which will now always include tip information.
+  * Removed `seccure` and `gmpy` dependencies
 
 
 ## [0.18.0] - 2017-11-08
diff --git a/INSTALL.md b/INSTALL.md
index b66814d26..b88b1291d 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -25,7 +25,7 @@ sudo pip install virtualenv
 On Ubuntu (we recommend 16.04), install the following:
 
 ```
-sudo apt-get install libgmp3-dev build-essential python2.7 python2.7-dev python-pip git python-virtualenv libssl-dev libffi-dev python-protobuf
+sudo apt-get install build-essential python2.7 python2.7-dev python-pip git python-virtualenv libssl-dev libffi-dev python-protobuf
 ```
 
 On Raspbian, you will also need to install `python-pyparsing`.
@@ -53,10 +53,7 @@ Currently, available binaries include:
 - Twisted
 - Zope.interface
 - pywin32
-- Yapsy
-- cx_Freeze
 - requests
-- gmpy
 
 Install the above binaries with `pip install *.whl`
 
diff --git a/build/build.ps1 b/build/build.ps1
index 1baa55a51..9785bcbf7 100644
--- a/build/build.ps1
+++ b/build/build.ps1
@@ -13,10 +13,8 @@ python setupmingw32.py install
 cd ..\
 Remove-Item -Recurse -Force miniupnpc-1.9
 
-# copy requirements from lbry, but remove gmpy and miniupnpc (installed manually)
-Get-Content ..\requirements.txt | Select-String -Pattern 'gmpy|miniupnpc' -NotMatch | Out-File requirements_base.txt
-# add in gmpy wheel
-Add-Content requirements.txt "./gmpy-1.17-cp27-none-win32.whl"
+# copy requirements from lbry, but remove miniupnpc (installed manually)
+Get-Content ..\requirements.txt | Select-String -Pattern 'miniupnpc' -NotMatch | Out-File requirements_base.txt
 
 python set_build.py
 
diff --git a/build/gmpy-1.17-cp27-none-win32.whl b/build/gmpy-1.17-cp27-none-win32.whl
deleted file mode 100644
index 5d15f0efa..000000000
Binary files a/build/gmpy-1.17-cp27-none-win32.whl and /dev/null differ
diff --git a/build/prebuild.sh b/build/prebuild.sh
index 7fa605cec..376e10752 100755
--- a/build/prebuild.sh
+++ b/build/prebuild.sh
@@ -41,7 +41,7 @@ set -eu
 
 if $LINUX; then
   INSTALL="$SUDO apt-get install --no-install-recommends -y"
-  $INSTALL build-essential libssl-dev libffi-dev libgmp3-dev python2.7-dev wget
+  $INSTALL build-essential libssl-dev libffi-dev python2.7-dev wget
 elif $OSX && ! cmd_exists brew ; then
   /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
 fi
diff --git a/lbrynet/core/cryptoutils.py b/lbrynet/core/cryptoutils.py
index 2528c7e69..6f71c9a69 100644
--- a/lbrynet/core/cryptoutils.py
+++ b/lbrynet/core/cryptoutils.py
@@ -1,18 +1,5 @@
-import seccure
 import hashlib
 
 
 def get_lbry_hash_obj():
     return hashlib.sha384()
-
-
-def get_pub_key(pass_phrase):
-    return str(seccure.passphrase_to_pubkey(pass_phrase, curve="brainpoolp384r1"))
-
-
-def sign_with_pass_phrase(m, pass_phrase):
-    return seccure.sign(m, pass_phrase, curve="brainpoolp384r1")
-
-
-def verify_signature(m, signature, pub_key):
-    return seccure.verify(m, signature, pub_key, curve="brainpoolp384r1")
diff --git a/requirements.txt b/requirements.txt
index a58308589..f1b3c0840 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,7 +10,6 @@ dnspython==1.12.0
 ecdsa==0.13
 envparse==0.2.0
 GitPython==2.1.3
-gmpy==1.17
 jsonrpc==1.2
 jsonrpclib==0.1.7
 jsonschema==2.6.0
@@ -25,7 +24,6 @@ PyGithub==1.34
 qrcode==5.2.2
 requests==2.9.1
 txrequests==0.9.5
-seccure==0.3.1.3
 service_identity==16.0.0
 six>=1.9.0
 slowaes==0.1a1
diff --git a/setup.py b/setup.py
index 801b61767..44111aecd 100644
--- a/setup.py
+++ b/setup.py
@@ -28,7 +28,6 @@ requires = [
     'pyyaml',
     'requests',
     'txrequests',
-    'seccure',
     'txJSON-RPC',
     'zope.interface',
     'docopt'