The game, which was dedicated to the memory of Tom Maynard, was dominated by the home side, who posted 219 for nine thanks to responsible knocks from Matthew Spriegel (51) and Kevin Pietersen (43).
In reply, the Welshmen collapsed from 55 for two to 77 for eight, with Gareth Batty taking three for four, before being skittled out for 126.
The match was played against a sombre backdrop as both sets of players recognised their former player Maynard, who died aged 23 on June 18 after being hit by a London Underground train.
The match marked the official launch of the Tom Maynard Trust and before play a posthumous county cap was awarded to his father, Matthew, by Surrey chairman Richard Thompson.
Matthew Maynard was joined by a host of recognised names, such as former England skipper Andrew Flintoff, who will this week embark on a 160-mile sponsored bike ride to the SWALEC stadium in Cardiff.
Meanwhile, in the County Championship, Rob Newton scored his second century of the season as Northamptonshire edged the first day of their match against Division Two leaders Derbyshire.
Newton made a brilliant 115 off 174 balls as Northamptonshire closed on 311 for six with his knock including 13 fours and one huge six over mid-wicket.
Teenager Shiv Thakor hit his third half-century in six innings as Leicestershire reached 334 for eight on the first day against Hampshire at Grace Road.
Thakor, a surprise omission from the England Under-19 World Cup squad, made a Championship-best 71 not out off 114 balls, to help Leicestershire fight back after slumping to 43 for three.