Pradosham is observed on the Trayodashi (13th day) of each lunar fortnight. As per the Hindu calendar Pradosham occurs twice in a month. i.e in Shukla Paksha and as well as in Krishna Paksha. people observe fast on this day and perform puja during the Pradosh kaal. God Shiva is worshipped on Pradosham day. What is Shani Pradosham? When a Pradosham falls on a Saturday, it is Called as Shani Pradosham. Saturday (Shanivaar) belongs to god Shani. Shani is the god, Who create the problems for human beings. People believe that by offering Shani pradosh vrat we can escape from ill effects of Shani. Pradhosha Purana: Once Dhevas and Asuras using the serpent Vasuki and the hill Mandhara were trying to get Amrutham (nector) from the Kseerabthi (milk ocean). Then the terrible poison Halahalam came up. All got frightened and pleaded to Lord Shiva for rescue. Being the peak of mercy Lord Shiva ate that poison. Then as per His order they resumed their effort to get Amrutham. They got it on Dhwadhasi (twelfth moon day). Without praying and thanking the God, by whom they got Amrutham, Devas started dancing and celebrating their victory. Significance Of Shani Pradosham Saturday is dedicated to Shanishwara, one of the Navagrahas. Lord Shani is widely believed to be the ruler of troubles and misfortunes. If pradosh happens to be on a Saturday, it is called as Shani Pradosh. People observe fasts and perform puja to appease Shani to get rid of bad effects. Few perfom yagna (Havan) on this day to to receive the grace of God Shiva and as well as God Shani. Shani Pradosh Vrat How to perform shani Pradosh Vrat?, Sani pradosh Vrat Vidhanam Devotees who observe Shani pradosh Vrat should wake up early, take bath, pray God Shiva, and fast during the day, and after bath in the Evening, perform Pujas to Lord Shiva.