A lighting system intended to be fitted to a swimming pool wall (P), said lighting system comprising: a) a wall feed-through element in the form of a cylindrical sleeve whose inner surface is provided with a female thread , b) a lighting device comprising: - a lighting support provided with a front face , a rear face and a through-hole , - lighting means integral with said front face of said lighting support , - means for fastening said lighting support to said wall feed-through element , and - a cable for the power supply of said lighting means , said power cable extending through said through-hole of said lighting support , characterized in that said wall feed-through element is intended to be fastened into the wall (P) of a swimming pool to delimit a through-passage of said wall (P), through which said cable is intended to extend, and in that said means for fastening said lighting support to said wall feed-through element comprise: - an interlock connector integral with said lighting support , provided with first interlock means (23a1), and - a fastening ring provided with a male thread (23b1) adapted to cooperate with said female thread of said wall feed-through element , said fastening ring including second interlock means (23b2) adapted to cooperate with said first interlock means (23a1) of said interlock connector . a) a wall feed-through element in the form of a cylindrical sleeve whose inner surface is provided with a female thread , b) a lighting device comprising: - a lighting support provided with a front face , a rear face and a through-hole , - lighting means integral with said front face of said lighting support , - means for fastening said lighting support to said wall feed-through element , and - a cable for the power supply of said lighting means , said power cable extending through said through-hole of said lighting support , characterized in that said wall feed-through element is intended to be fastened into the wall (P) of a swimming pool to delimit a through-passage of said wall (P), through which said cable is intended to extend, and in that said means for fastening said lighting support to said wall feed-through element comprise: - an interlock connector integral with said lighting support , provided with first interlock means (23a1), and - a fastening ring provided with a male thread (23b1) adapted to cooperate with said female thread of said wall feed-through element , said fastening ring including second interlock means (23b2) adapted to cooperate with said first interlock means (23a1) of said interlock connector . - a lighting support provided with a front face , a rear face and a through-hole , - lighting means integral with said front face of said lighting support , - means for fastening said lighting support to said wall feed-through element , and - a cable for the power supply of said lighting means , said power cable extending through said through-hole of said lighting support , - an interlock connector integral with said lighting support , provided with first interlock means (23a1), and - a fastening ring provided with a male thread (23b1) adapted to cooperate with said female thread of said wall feed-through element , <EOS>