Number of Deadlocks/sec reached to 1200

Hi All,

We have a SQL Server 2005 (SP4) instance, recently we have received alert saying Number of Deadlocks/sec: 1200, this is a critical alert. I have verifyed this using 

SELECT cntr_value AS NumOfDeadLocks,*
  FROM sys.dm_os_performance_counters
 WHERE object_name = 'SQLServer:Locks'
   AND counter_name = 'Number of Deadlocks/sec'
   AND instance_name = '_Total'

I am new to performance tuning, Could you please suggest how to resolve this.

Thanks in advance,

KR