An effort of formulating, implementing and testing new parton shower Monte Carlo for W/Z production at Large Hadron Collider (LHC) is presented. In particular, it is indicated how to construct a constrained Monte Carlo (CMC) parton shower algorithm implementing the CCFM-like evolution for a single hadron beam and how to combine two such CMCs into the single MC simulating initial state QCD radiation. Preliminary numerical results are presented.

PACS numbers: 12.38.--t, 12.38.Bx, 12.38.Cy