First-quarter revenue was Tw$42.8 billion ($1.45 billion) and net profit slumped 98.1 percent year-on-year to a record low of Tw$85 million.
But chief executive officer Peter Chou forecast that second-quarter revenue would surge more than 60 percent compared to the first quarter, to Tw$70 billion.
"This was a pivotal quarter for HTC," he told an investor conference.
"In February our teams set a new standard for smartphones, launching the new HTC One (Review I Pictures). The reviews of fans and critics alike have been overwhelmingly positive and we look forward to delivering on the promise of this device."
The Android-based model, sporting a 4.7-inch (12 cm) touchscreen and front-facing speakers, was unveiled in London and New York in February .
Chou had hailed it as a "technological breakthrough" as he battles fierce competition from the Apple iPhone and Samsung's newly released Galaxy S4.
However the firm has a tough fight on its hands.
Research firm IDC said HTC held a 4.6 percent share of the global smartphone market in 2012, a sharp decline from 8.8 percent a year earlier. Samsung held a 30.3 percent stake while Apple had 19.1 percent.
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