diff --git a/lib/node.js b/lib/node.js
index 6a8e799..cdf615f 100644
--- a/lib/node.js
+++ b/lib/node.js
@@ -339,7 +339,7 @@ Node.prototype.setUptime = function()
 
 Node.prototype.formatBlock = function (block)
 {
-	if( !_.isUndefined(block) && !_.isUndefined(block.number) && block.number >= 0 && !_.isUndefined(block.difficulty) && !_.isUndefined(block.totalDifficulty) )
+	if( !_.isNull(block) && !_.isUndefined(block) && !_.isUndefined(block.number) && block.number >= 0 && !_.isUndefined(block.difficulty) && !_.isUndefined(block.totalDifficulty) )
 	{
 		block.difficulty = block.difficulty.toString(10);
 		block.totalDifficulty = block.totalDifficulty.toString(10);