The spiritual world of the Isneg is populated by more than 300 anito (spirits) who assume various forms. There are actually no gods or hierarchical deities in the otherworld of the Isneg, only good or bad spirits.
- Anlabban - The spirit who looks after the general welfare of the people and is recognized as the special protector of hunters.
- Bago - The spirit of the forest.
- Sirinan - The river spirit.
- Landusan - Held responsible for some cases of extreme poverty. Those believed to be suffering from the machinations of this spirit are said to be malandusan (impoverished).
There are spirits who come to help the reapers in gathering the harvest. They are known as Abad, Aglalannawan, Anat, Binusilan, Dawiliyan, Dekat, Dumingiw, Imbanon, Gimbanona, Ginalinan, Sibo, and a group of sky dwellers collectively known as the Ilanit.
- Alupundan - Causes the reapers' toes to get sore all over and swell.
- Arurin - She sees to it that the harvest is bad, if the Isneg farmers fail to give her share.
- Dagdagamiyan - A female spirit who causes sickness in children for playing in places where the harvest is being done.
- Darupaypay - Devours the palay stored in the hut before it is transferred to the granary.
- Ginuudan - Come to measure the containers of palay, and causes it to dwindle.
- Sildado - Resembles a horse, and kills children who play noisily outside the house.
- Inargay - Kills people during harvest time. When inapugan, a ritual plant is offered to Inargay, the following prayer is recited by the Isneg farmer: "Iapugko iyaw Inargay ta dinaami patpatay" (I offer this betel to you, Inargay, so that you may not kill us).
- Alipugpug - A good harvest is portended by the rising of a little whirlwind from the burned field. This, it is said, is the spirit of Alipugpug.
- Pilay - Rice pudding is offered to Pilay, the spirit of the rice, who resides on the paga, a shelf above the Isneg hearth. This is the pisi, the ritual offering of food to the spirits. The old woman who performs this utters the following prayer: "Ne uwamo ilay ta ubatbattugammo ya an-ana-a, umaammo ka mabtugda peyan" (Here, this is yours, Pilay, so that you feed my children fully, and make sure that they are always satisfied). Another ritual is performed right in the fields where the harvest is going on. The amulets inapugan, takkag (a kind of fern), and herbs are tied to a stalk of palay, which later will be place in the granary before the other palay. Again, these are reserved for Pilay. In case a new granary is built, and the contents of the old granary transferred, the spirit's special share is also transferred to the new place. It is never consumed.