"It's another result where they have shown pretty strong sales and earnings growth," Harbour Asset Management senior analyst Oyvinn Rimer said.
"Compared to other companies in Australia and New Zealand, it's remarkable growth, but there has been a miss on what the market was expecting," he said.
A consensus of market expectations was for a net profit of $297m.
The company's earnings before interest, tax, depreciation and amortisation (EBITDA) jumped by 46.1 per cent to $413.6m.
The earnings increase was driven by a 41.4 per cent lift in turnover to $1.31 billion.
Its infant nutrition market share strengthened to 6.4 per cent in China.
A2 Milk said revenue from the Australian fresh milk market revenue grew by 10.7 per cent and its market share there rose to 11.2 per cent.
Group infant formula revenue came to $1.06 billion, up 46.9 per cent.
US milk revenue more than doubled and distribution expanded to 13,100 stores.
A2 Milk's cash on hand came to $464.8m.
Chief executive and managing director Jayne Hrdlicka said the business continued to build.
"The company's record financial and market share results for 2019 was enabled by strong revenue growth across our key product segments of liquid milk, infant nutrition and other nutritional milk products, and across each of our key regions," she said in a statement.
"Results were underpinned by growing brand awareness, expanding product distribution and strengthening in-market execution in our two most important regions of Greater China and the US," Hrdlicka said.
"We have focused on really getting to know our consumers and sales channels in our core markets of China and the US," she said.
A2 Milk has invested heavily in increasing its capability and capacity.
"In effect much of our effort in 2019 was spent balancing our dual priorities of sustaining our growth momentum in the year while at the same time deepening our local consumer and market knowledge, investing to build capability and creating detailed blueprints to deliver future growth," she said.
The results were driven by strong performance across a2 Milk's portfolio.
"The continued growth of our infant nutrition products was a strong contributor to the results with sales totalling $1.1 billion for the year — an increase of 46.9 per cent on the prior year. This was driven by share gains in China and Australia," Hrdlicka said.
There had been "pleasing growth" in a2 Milk's liquid milk businesses in particular within Australia and the US — with total fresh milk growth of 22.9 per cent and revenue of $174.9m across the group.
A2 Milk's gross margin remained strong and had improved to 54.7 per cent.
"Our balance sheet continues to strengthen, which is important as we work our way through the delivery requirements of our long-term strategy," she said.
A2 Milk finished the year with $108.5m of inventory, up 69.2 per cent from the prior corresponding period and 49 per cent from the first half.
