At the heart of the restructure is the abolition of Lego's divisional structure for Europe, which was previously split into Central, Northern and Southern arms.
Europe will now operate as a single division within Lego's global structure, with Poulsen expected to unveil his senior management team in the coming weeks. Lego chief operating officer Paul Ploughmann has been forced out as a result of the restructure.
Mads Nipper, who was senior vice-president for Lego Central Europe, will take on Poulsen's former responsibility for global marketing and innovation.
Further senior marketing appointments are expected this month.
Last week Lego announced annual losses of 1.4bn DKK (£129m), blaming a 25% decline in global sales of Lego in 2003 and deteriorating market share in key territories.