Club president Fraser Skinner said volunteers had spent three weekends working on the 50sq m building.
The pavilion will boast changing rooms, toilets, and a ''place to store all the trophies'' after the Queenstown Lakes District Council approved the project in March.
The ground was developed for cricket about 18 years ago and while the initial proposal put to the council last February was for toilets to be built on the ground, Mr Skinner said there would be greater benefits in constructing a bigger building to cater for senior and junior cricketers and any other community groups who wanted to use it.
The building was designed by Matt White and construction began three weeks ago, helped by input from a small army of volunteers, some with no affiliation to the club.
A group of builders turned out again on Saturday to construct the deck and line the building, which could be completed by the end of February.
Mr Skinner said the club had also been helped by Placemakers, which offered ''competitive'' rates for building supplies.
''It's been one of those great, feel-good projects.''
Landscaping design was done by Paddy Baxter, who would also be incorporating nets into the ground design in an effort to ''turn the Millbrook Cricket Club around''.
''One of our focuses is to encourage growth of cricket in the area.''
The total budgeted cost of the project, reported to the council in May, was $103,900 plus GST, with the council's contribution totalling $85,000, including $35,000 for design, consents, services and fittings and up to $50,000 in materials.
Mr Skinner said the club was also being supported by the Peter Wilding Trust.