diff --git a/kong/plugins/log-serializers/alf.lua b/kong/plugins/log-serializers/alf.lua
index f38baaab385..fe8a3f8322d 100644
--- a/kong/plugins/log-serializers/alf.lua
+++ b/kong/plugins/log-serializers/alf.lua
@@ -17,6 +17,8 @@
 
 local stringy = require "stringy"
 
+local ngx_encode_base64 = ngx.encode_base64
+
 local EMPTY_ARRAY_PLACEHOLDER = "__empty_array_placeholder__"
 
 -- Transform a key/value lua table into an array of elements with `name`, `value`.
@@ -67,6 +69,9 @@ function _M.serialize_entry(ngx)
   local alf_res_body = analytics_data.res_body or ""
   local alf_req_post_args = analytics_data.req_post_args or {}
 
+  local alf_base64_req_body = ngx_encode_base64(alf_req_body)
+  local alf_base64_res_body = ngx_encode_base64(alf_res_body)
+
   -- timers
   local proxy_started_at, proxy_ended_at = ngx.ctx.proxy_started_at, ngx.ctx.proxy_ended_at
 
@@ -130,7 +135,7 @@ function _M.serialize_entry(ngx)
       postData = {
         mimeType = alf_req_mimeType,
         params = dic_to_array(alf_req_post_args),
-        text = alf_req_body
+        text = alf_base64_req_body
       }
     },
     response = {
@@ -145,7 +150,7 @@ function _M.serialize_entry(ngx)
       content = {
         size = tonumber(ngx.var.body_bytes_sent),
         mimeType = alf_res_mimeType,
-        text = alf_res_body
+        text = alf_base64_res_body
       }
     },
     cache = {},
diff --git a/kong/tools/ngx_stub.lua b/kong/tools/ngx_stub.lua
index 4d0b0b66320..c5d9c202f09 100644
--- a/kong/tools/ngx_stub.lua
+++ b/kong/tools/ngx_stub.lua
@@ -26,6 +26,9 @@ _G.ngx = {
       return res_str, sub_made
     end
   },
+  encode_base64 = function(str)
+    return string.format("base64_%s", str)
+  end,
   -- Builds a querystring from a table, separated by `&`
   -- @param `tab`          The key/value parameters
   -- @param `key`          The parent key if the value is multi-dimensional (optional)
diff --git a/spec/plugins/mashape-analytics/alf_serializer_spec.lua b/spec/plugins/mashape-analytics/alf_serializer_spec.lua
index f3eff8354e4..b75e2f0a86e 100644
--- a/spec/plugins/mashape-analytics/alf_serializer_spec.lua
+++ b/spec/plugins/mashape-analytics/alf_serializer_spec.lua
@@ -1,3 +1,4 @@
+require "kong.tools.ngx_stub"
 local fixtures = require "spec.plugins.mashape-analytics.fixtures.requests"
 local ALFSerializer = require "kong.plugins.log-serializers.alf"
 
diff --git a/spec/plugins/mashape-analytics/fixtures/requests.lua b/spec/plugins/mashape-analytics/fixtures/requests.lua
index b0f05cf8600..b861bb394fd 100644
--- a/spec/plugins/mashape-analytics/fixtures/requests.lua
+++ b/spec/plugins/mashape-analytics/fixtures/requests.lua
@@ -52,7 +52,7 @@ return {
             {name = "hello", value = "world"},
             {name = "hello", value = "earth"}
           },
-          text = "hello=world&hello=earth"
+          text = "base64_hello=world&hello=earth"
         },
         queryString = {
           {name = "foo", value = "bar"},
@@ -66,7 +66,7 @@ return {
         content = {
           mimeType = "application/json",
           size = 934,
-          text = "{\"message\":\"response body\"}"
+          text = "base64_{\"message\":\"response body\"}"
         },
         cookies = {EMPTY_ARRAY_PLACEHOLDER},
         headers = {
@@ -144,7 +144,7 @@ return {
             {name = "hello", value = "world"},
             {name = "hello", value = "earth"}
           },
-          text = "hello=world&hello=earth"
+          text = "base64_hello=world&hello=earth"
         },
         queryString = {
           {name = "foo", value = "bar"},
@@ -157,7 +157,7 @@ return {
         content = {
           mimeType = "application/json",
           size = 934,
-          text = "{\"message\":\"response body\"}"
+          text = "base64_{\"message\":\"response body\"}"
         },
         cookies = {EMPTY_ARRAY_PLACEHOLDER},
         headers = {