Yes there are some laws and qualifiactions you will need to use a drone commercially.
You will need to obtain a BUNC qualification to use a quadcopter commercially. You can find out more about that here http://www.eurousc.com/pilot-qualification-(bnuc-std).html
The BNUC qualification is gained by passing a Part 1 Ground Examination and Part 2 Flight Operation Assessment. Further details can be found in the Candidate Guide.
You can also see some general notes on the regulations and general safety here http://www.unmannedtech.co.uk/regulations.html
For commerial work here are the qualifications required and permission for the various UAV sizes.