Revised yearly, the list ranks the 50 countries where Christians face the most extreme persecution based on restrictions on private, family, community, national and church life, as well as the number of violent acts.
Here are the top ten:
1. North Korea
2. Afghanistan
3. Somalia
4. Sudan
5. Pakistan
6. Eritrea
7. Libya
8. Iraq
9. Yemen
10. Iran
North Korea has topped the list again as the most dangerous place for Christians to live.
Around 70,000 Christians are believed to be in labour camps after being caught worshipping.
A crackdown on Christianity also worsened last year in the secretive state due to the North Korean regime monitoring the border with China closely and raiding safe houses where Christian converts have sought refuge.
As well as expressing deepening concern for Christians in North Korea, Open Doors has also drawn attention to believers in Egypt and Turkey after "unprecedented levels of persecution and suppression".
Egypt was placed 17th on the new Open Doors World Watch List nine places higher than its ranking 2014.
Turkey, which did not appear on the Open Doors World Watch List in 2014, entered the ranking in 2015 (ranked 41st), before rising to 31st in 2018.
Open Doors UK and Ireland CEO Lisa Pearce said the Christians in both countries are resilient despite extreme discrimination and intimidation.
She said: "It is hard for us here in the UK and Ireland to imagine being defined by our religion every single day in every sphere of life.
"In Egypt, as in many other Middle Eastern countries, your religion is stated on your identity card.
"This makes discrimination and persecution easy - you are overlooked for jobs, planning permits are hard to obtain and you are a target when you go to church."
In 2017, there were numerous violent attacks across Egypt, including at Easter when 49 people were killed in two church bombings and in May when Islamic extremists attacked people travelling to a monastery in Upper Egypt, killing 29.
Also this year, Nepal entered the World Watch List at number 25th - as extreme persecution by Hindu religious nationalists continues.
Looking forward, Open Doors is keeping a watchful eye on South East Asia and has dubbed it the next emerging persecution hotbed.
The charity said it has noticed a rise in persecution fuelled by Islamic extremism in Malaysia, Indonesia, the Philippines and the Maldives.