By AppleInsider Staff

Published: 04:35 PM EST (01:35 PM PST)

Apple said Monday that fourth quarter profits rose more than 70% to $4.31 billion, or $4.64 per diluted share, driven by record sales in three of its four major product categories.

The Cupertino-based company posted record revenue of $20.34 billion and net quarterly profit of $4.31 billion, or $4.64 per diluted share. These results compare to revenue of $12.21 billion and net quarterly profit of $2.53 billion, or $2.77 per diluted share, in the year-ago quarter.

Gross margin was 36.9 percent compared to 41.8 percent in the year-ago quarter. International sales accounted for 57 percent of the quarter’s revenue.

“We’re thrilled with the performance and strength of our business, generating almost $5.7 billion in cash flow from operations during the quarter,” said Peter Oppenheimer, Apple’s CFO. “Looking ahead to the first fiscal quarter of 2011, we expect revenue of about $23 billion and we expect diluted earnings per share of about $4.80.”

Apple sold a record 3.89 million Macs during the quarter, a 27 percent unit increase over the year-ago quarter. It also sold a record 14.1 million iPhones in the quarter, representing 91 percent unit growth over the year-ago quarter.

In total, the company shipped 9.05 million iPods during the quarter, representing an 11 percent unit decline from the year-ago quarter, as well as 4.19 million iPads, another record quarterly shipment.

“We are blown away to report over $20 billion in revenue and over $4 billion in after-tax earnings—both all-time records for Apple,” said Steve Jobs, Apple’s CEO. “iPhone sales of 14.1 million were up 91 percent year-over-year, handily beating the 12.1 million phones RIM sold in their most recent quarter. We still have a few surprises left for the remainder of this calendar year.”

Apple hold its Q4 2010 financial results conference call beginning at 2:00 p.m. PDT (5:00 PM Eastern) today and AppleInsider will have full coverage.