Yes there is, this was not a hard question, I dont know why you didnt get an answer.  

To see who has logged into QB, Credit Card Audit Trail feature must be enabled (Company > Customer Credit Card Protection > Enable Protection).  Once the Credit Card Protection feature is turned on, it cannot be turned off and requires a strong password which must be changed every 90 days.  When enabled, user logins are recorded in the Credit Card Audit Trail Report (Reports > Accountant & Taxes > Customer Credit Card Audit Trail).