Voting began early on Saturday at more 2,000 polling stations across the landlocked mountain kingdom, which is surrounded by South Africa.
Delays occurred at some polling stations being inspected by police explosives units and sniffer dogs.
Al Jazeera's Erica Wood, reporting from the outskirts of Maseru, the capital of Lesotho, said many voters expressed frustration with the ongoing political crisis and were hoping the situation would improve after elections.
"There is an optimism that with international observers and security present that this election will be peaceful and bring about change," our correspondent said.
The country has been politically deadlocked since Prime Minister Thomas Thabane suspended parliament in June last year to avoid a motion that would have seen him ousted after his fragile coalition government, in power since 2012, fell apart