  For every positive integer $k$, we show that every graph of order $n$ at
least $3k$ with more than $$\max\{{2k-1\choose 2}+(2k-1)(n-(2k-1)),{3k-1\choose
2}+(n-(3k-1))\}$$ edges has $k$ vertex disjoint cycles, which is a best
possible density version of a theorem of Corr\'{a}di and Hajnal.
