The Chief Minister administered the oath of office and secrecy to the new appointees at the state secretariat.
With this, the total number of CPS in the Congress-ruled state has risen to nine.
The Chief Parliamentary Secretaries are of the rank of Minister of State and are in addition to the eleven Cabinet ministers, including the Chief Minister.
Talking to reporters after the ceremony, Singh said the lone vacancy in the Cabinet would be filled at an appropriate time.
Among the new CPS are Jagjivan Pal, a two-time MLA from Sulah and Rakesh Kalia, elected twice to the Assembly from Chintpurni in the past. He represents Gagret constituency in Una district.
Also inducted were Sohan Lal, two-time sitting MLA from Sundernagar in Mandi district and Rohit Thakur, the grandson of former chief minister Ram Lal Thakur and the sitting MLA from Jubbal and Kotkhai.
Inder Dutt Lakhanpal, a first-time MLA from Badsar in Hamirpur district, was also sworn-in.