The GMB union said 600 members walked out at 06:30 BST and will not return until Tuesday, with further action due to take place from 21 to 23 April.
Members are calling for a pay rise from £10.50 to £15 an hour, although the union is not recognised by the US firm.
Amazon had previously said that minimum pay had recently risen by 10% and by more than 37% since 2018.
A spokesperson for the online retailer said it carried out regular reviews of its pay to "ensure we offer competitive wages", adding that only a "tiny proportion" of its workforce in Coventry was involved in the dispute.
More than 100 union members were said to have joined the picket line outside the Amazon warehouse in Coventry on Sunday, according to GMB representatives.
Amanda Gearing, GMB senior organiser, said: "GMB members are worth more; they will not accept a pay rise of pennies from one of the world's wealthiest corporations
She added: "The atmosphere is great, it's one of determination to succeed. The workers feel they have no other choice, they are all facing financial hardship."
Cars can be seen lined up outside of the warehouse in Coventry