The world's second-biggest television set maker behind compatriot Samsung Electronics estimated profit of 75.3 billion won ($67.03 million) for October-December last year. That would compare with the 387 billion won average of 11 analyst estimates in an I/B/E/S Refinitiv poll.
Revenue likely fell 7 percent to 15.8 trillion won, LG said in a regulatory filing, versus analysts' 16.3 trillion won estimate.
LG did not disclose further details of fourth-quarter operations and will announce full results at the end of January.
Analysts said earnings were likely weighed down by higher year-end bonuses and marketing expenses for new smartphones.
LG held a 3 percent share of the global smartphone market in the second quarter of last year, showed latest data from market tracker Counterpoint Research.
Earlier in the day, Samsung estimated a 29 percent drop in quarterly profit, its first decline in two years, as it flagged tough memory chip and mobile phone markets.