Two providers are failing to meet the needs of their learners, and the remainder only provide an "adequate" service.
Chief inspector of ALI, David Sherlock said: "We inspect without fear or favour. And, as these first reports show, we will not shrink from telling it like it is.
"Adult learning in England has to improve if we're to compete globally. It's our job to make sure that happens.
"Quality is very mixed. There are some good aspects of provision, but some is unsatisfactory and even very weak. In the case of two of the first five providers to be inspected, the overall quality of provision is not adequate to meet the needs of those receiving it."
The ALI inspected the Dorset New Deal Unit of Delivery in Dorchester, Sefton New Deal Unit of Delivery in Merseyside, Channel New Deal Unit of Delivery in Folkestone, Kent, Lambeth Emploment Training Scheme in London, and EMTA Cleveland Training Centre in Billingham.
A grade of 1 is judged as "outstanding" and 5 is "very weak." Overall, leadership and management were judged mediocre. Lambeth got a grade 5, and Sefton a 4. Only one grade 2 was awarded.
Margaret Hodge, minister for lifelong learning and higher education, said she hoped the work of the inspectors would raise standards. "There is clearly much work we need to do to ensure learners enjoy quality training. Where providers are not offering quality across the board, they must act to rectify this. We know they may not be able to deliver a rapid change in the quality of their service without help.
"The Learning and Skills Council and Employment Service will help work based learning providers develop post-inspection action plans to address weaknesses, but build on the strengths."
The five reports are the first from more than 100 inspections undertaken by the ALI since 1 April.